We've kind of fallen into the literals and the serious nerves.
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And the literals will, you know, read about the tweets and the Times and elsewhere.
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You'll get to grips with key components like functions, arrays, objects, loops, and conditionals, and core functionality like math, strings, literals identifiers, and more.
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Narrowly speaking, here documents are file literals or stream literals. These originate in the Unix shell, though similar facilities are available in some other languages.
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Adjacent string literal tokens are concatenated." and 2.14.5 String literals [lex.string], note 13, p. 28–29: "In translation phase 6 (2.2), adjacent string literals are concatenated.
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The revision operator by Weber is similar, but the literals that are removed from K are not all literals of P, but only the literals that are evaluated differently by a pair of closest models of K and P according to the Satoh measure of closeness.
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Literals are often used to initialize variables, for example, in the following, 1 is an integer literal and the three letter string in "cat" is a string literal: int a = 1; string s = "cat"; In lexical analysis, literals of a given type are generally a token type, with a grammar rule, like "a string of digits" for an integer literal. Some literals are specific keywords, like `true` for the boolean literal "true". In some object-oriented languages (like ECMAScript), objects can also be represented by literals. Methods of this object can be specified in the object literal using function literals.
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An instance of this non-uniform problem can be then written as a set of literals of the form R_i(x_1,\ldots,x_n). Among these instances/sets of literals, some are satisfiable and some are not; whether a set of literals is satisfiable depends on the relations, which are specified by the non-uniform problem. In the other way around, a non-uniform problem tells which sets of literals represent satisfiable instances and which ones represent unsatisfiable instances. Once relations are named, a non- uniform problem expresses a set of sets of literals: those associated to satisfiable (or unsatisfiable) instances.
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This article is a list of Literals and Part-Literals in the Vertigo comic book series Fables, Jack of Fables, Cinderella: From Fabletown with Love, Cinderella: Fables Are Forever and Fairest, published by DC Comics.
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The Teiresias algorithm uses regular expressions to define the patterns. This allows the patterns reported to consist not only from the characters that appear in each position (literals) but from a specific group of characters (bracketed literals) or even from any character (wild card). The patterns created by the algorithm are patterns that have at least k instances in the input, where L ≤ W and L, W, k positive integers. A pattern is called an pattern if and only if any L consecutive literals or bracketed literals span at most W positions (i.e.
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RFC 7405 updates it, adding a syntax for specifying case-sensitive string literals.
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These also allow initial tabs to be stripped via the variant syntax `<<-END` though leading spaces are not stripped. The same syntax has since been adopted for multiline string literals in a number of languages, most notably Perl, and are also referred to as here documents, and retain the syntax, despite being strings and not involving redirection. As with other string literals, these can sometimes have different behavior specified, such as variable interpolation. Python, whose usual string literals do not allow literal newlines, instead has a special form of string, designed for multiline literals, called triple quoting.
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Another similar problem is C programming language's control characters of string literals, like `printf("Hello, world.¥n");`.
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The class of conjunctions and the class of disjunctions are evolvable over the uniform distribution for short conjunctions and disjunctions, respectively. The class of parity functions (which evaluate to the parity of the number of true literals in a given subset of literals) are not evolvable, even for the uniform distribution. Evolvability implies PAC learnability.
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In Boolean logic, a product term is a conjunction of literals, where each literal is either a variable or its negation.
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Pure literals can always be assigned in a way that makes all clauses containing them true. Thus, these clauses do not constrain the search anymore and can be deleted. Unsatisfiability of a given partial assignment is detected if one clause becomes empty, i.e. if all its variables have been assigned in a way that makes the corresponding literals false.
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In many languages, string literals can contain literal newlines, spanning several lines. Alternatively, newlines can be escaped, most often as ` `. For example: echo 'foo bar' and echo -e "foo bar" are both valid bash, producing: foo bar Languages that allow literal newlines include bash, Lua, Perl, PHP, R, and Tcl. In some other languages string literals cannot include newlines.
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Some programming languages also provide other ways to represent special characters in literals, without requiring an escape character (see e.g. delimiter collision).
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Some programming languages, like Pascal, use the ASCII apostrophe to delimit string literals. In many languages, including JavaScript, ECMAScript, and Python, either the apostrophe or the double quote may be used, allowing string literals to contain the other character (but not to contain both without using an escape character), e.g. `foo = 'He said "Bar!"';`. Strings delimited with apostrophes are often called single quoted.
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All C++11 features are supported except for concurrency and atomic operations, and user-defined literals. Version 12.6 supports the C++14 language standard.
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Another variant is the not-all-equal 3-satisfiability problem (also called NAE3SAT). Given a conjunctive normal form with three literals per clause, the problem is to determine if an assignment to the variables exists such that in no clause all three literals have the same truth value. This problem is NP-complete, too, even if no negation symbols are admitted, by Schaefer's dichotomy theorem.
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In C, string literals are surrounded by double quotes (), e.g. and are compiled to an array of the specified values with an additional null terminating character (0-valued) code to mark the end of the string. String literals may not contain embedded newlines; this proscription somewhat simplifies parsing of the language. To include a newline in a string, the backslash escape may be used, as below.
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A sufficient condition of tractability is that a non-uniform problem is tractable if the set of its unsatisfiable instances can be expressed by a Boolean Datalog query. In other words, if the set of sets of literals that represent unsatisfiable instances of the non-uniform problem is also the set of sets of literals that satisfy a Boolean Datalog query, then the non-uniform problem is tractable.
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In Boolean logic, a formula is in conjunctive normal form (CNF) or clausal normal form if it is a conjunction of one or more clauses, where a clause is a disjunction of literals; otherwise put, it is a product of sums or an AND of ORs. As a canonical normal form, it is useful in automated theorem proving and circuit theory. All conjunctions of literals and all disjunctions of literals are in CNF, as they can be seen as conjunctions of one-literal clauses and conjunctions of a single clause, respectively. As in the disjunctive normal form (DNF), the only propositional connectives a formula in CNF can contain are and, or, and not.
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However, since for any k ≥ 3, this problem can neither be easier than 3-SAT nor harder than SAT, and the latter two are NP-complete, so must be k-SAT. Some authors restrict k-SAT to CNF formulas with exactly k literals. This doesn't lead to a different complexity class either, as each clause with j < k literals can be padded with fixed dummy variables to . After padding all clauses, 2k-1 extra clausesviz.
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SAT is easier if the number of literals in a clause is limited to at most 2, in which case the problem is called 2-SAT. This problem can be solved in polynomial time, and in fact is complete for the complexity class NL. If additionally all OR operations in literals are changed to XOR operations, the result is called exclusive-or 2-satisfiability, which is a problem complete for the complexity class SL = L.
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Words include reserved words and user-defined identifiers. They are up to 31 characters long and may include letters, digits, hyphens and underscores. Literals include numerals (e.g. ) and strings (e.g. ).
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Values used as constraints can either be literals used in the PDU specification, or ASN.1 values specified elsewhere in the schema file. Some ASN.1 tools will make these ASN.
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A sufficient condition for tractability is related to expressibility in Datalog. A Boolean Datalog query gives a truth value to a set of literals over a given alphabet, each literal being an expression of the form L(a_1,\ldots,a_n); as a result, a Boolean Datalog query expresses a set of sets of literals, as it can be considered semantically equivalent to the set of all sets of literals that it evaluates to true. On the other hand, a non-uniform problem can be seen as a way for expressing a similar set. For a given non-uniform problem, the set of relations that can be used in constraints is fixed; as a result, one can give unique names R_1,\ldots,R_n to them.
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A propositional knowledge base KB is vivid iff KB is a complete and consistent set of literals (over some vocabulary).Knowledge Representation and Reasoning / Ronald J. Brachman, Hector J. Levesque / page 337 Such a knowledge base has the property that it as exactly one interpretation, i.e. the interpretation is unique. A check for entailment of a sentence can simply be broken down into its literals and those can be answered by a simple database-like check of KB.
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This is the Self version of the hello world program. The `'` syntax indicates a literal string object. Other literals include numbers, blocks and general objects. Grouping can be forced by using parentheses.
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An important variation used in the study of computational complexity is k-DNF. A formula is in k-DNF if it is in DNF and each conjunction contains at most k literals.
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Datatype properties are relations between instances of classes and RDF literals or XML schema datatypes. For example, modelName (String datatype) is the property of Manufacturer class. They are formulated using owl:DatatypeProperty type.
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In some languages, integer literals may contain digit separators to allow digit grouping into more legible forms. If this is available, it can usually be done for floating point literals as well. This is particularly useful for bit fields, and makes it easier to see the size of large numbers (such as a million) at a glance by subitizing rather than counting digits. It is also useful for numbers that are typically grouped, such as credit card number or social security numbers.
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The unit clauses that are present in a set of clauses or can be derived from it can be stored in form of a partial model (this partial model may also contain other literals, depending on the application). In this case, unit propagation is performed based on the literals of the partial model, and unit clauses are removed if their literal is in the model. In the example above, the unit clause a would be added to the partial model; the simplification of the set of clauses would then proceed as above with the difference that the unit clause a is now removed from the set. The resulting set of clauses is equivalent to the original one under the assumption of validity of the literals in the partial model.
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In Ada, C# (from version 7.0), D, Eiffel, Haskell (from GHC version 8.6.1), Java (from version 7), Julia, Perl, Python (from version 3.6), Ruby, Rust and Swift, integer literals and float literals can be separated with an underscore (`_`). There can be some restrictions on placement; for example, in Java they cannot appear at the start or end of the literal, nor next to a decimal point. Note that while the period, comma, and (thin) spaces are used in normal writing for digit separation, these conflict with their existing use in programming languages as radix point, list separator (and in C/C++, the comma operator), and token separator. Examples include: int oneMillion = 1_000_000; int creditCardNumber = 1234_5678_9012_3456; int socialSecurityNumber = 123_45_6789; In C++14 (2014), the apostrophe character may be used to separate digits arbitrarily in numeric literals.
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As with other literals, integer literals are generally evaluated at compile time, as part of the semantic analysis phase. In some cases this semantic analysis is done in the lexer, immediately on recognition of an integer literal, while in other cases this is deferred until the parsing stage, or until after the parse tree has been completely constructed. For example, on recognizing the string `0x10` the lexer could immediately evaluate this to 16 and store that (a token of type `integer` and value 16), or defer evaluation and instead record a token of type `integer` and value `0x10`. Once literals have been evaluated, further semantic analysis in the form of constant folding is possible, meaning that literal expressions involving literal values can be evaluated at the compile phase.
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As an inline file, these are semantically similar to here documents, though there can be only one per script. However, in these languages the term "here document" instead refers to multiline string literals, as discussed below.
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While sigils are applied to names (identifiers), similar prefixes and suffixes can be applied to literals, notably integer literals and string literals, specifying either how the literal should be evaluated, or what data type it is. For example, `0x10ULL` evaluates to the value 16 as an unsigned long long integer in C++: the `0x` prefix indicates hexadecimal, while the suffix `ULL` indicates unsigned long long. Similarly, prefixes are often used to indicate a raw string, such as `r"C:\Windows"` in Python, which represents the string with value `C:\Windows`; as an escaped string this would be written as `"C:\\Windows"`. As this affects the semantics (value) of a literal, rather than the syntax or semantics of an identifier (name), this is neither stropping (identifier syntax) nor a sigil (identifier semantics), but it is syntactically similar.
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Right: A simpler reduction with the same properties. A variant of the 3-satisfiability problem is the one-in-three 3-SAT (also known variously as 1-in-3-SAT and exactly-1 3-SAT). Given a conjunctive normal form with three literals per clause, the problem is to determine whether there exists a truth assignment to the variables so that each clause has exactly one TRUE literal (and thus exactly two FALSE literals). In contrast, ordinary 3-SAT requires that every clause has at least one TRUE literal.
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A given constraint logic program may be reformulated to improve its efficiency. A first rule is that labeling literals should be placed after as much constraints on the labeled literals are accumulated in the constraint store. While in theory is equivalent to , the search that is performed when the interpreter encounters the labeling literal is on a constraint store that does not contain the constraint `X>0`. As a result, it may generate solutions, such as `X=-1`, that are later found out not to satisfy this constraint.
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Two issues with multiline string literals are leading and trailing newlines, and indentation. If the initial or final delimiters are on separate lines, there are extra newlines, while if they are not, the delimiter makes the string harder to read, particularly for the first line, which is often indented differently from the rest. Further, the literal must be unindented, as leading whitespace is preserved – this breaks the flow of the code if the literal occurs within indented code. The most common solution for these problems is here document- style string literals.
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For the related MAX-E3SAT problem, in which all clauses in the input 3SAT formula are guaranteed to have exactly three literals, the simple randomized approximation algorithm which assigns a truth value to each variable independently and uniformly at random satisfies 7/8 of all clauses in expectation, irrespective of whether the original formula is satisfiable. Further, this simple algorithm can also be easily derandomized using the method of conditional expectations. The Karloff–Zwick algorithm, however, does not require the restriction that the input formula should have three literals in every clause.
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For example, in the statement `x = 2 + 2` after the literals have been evaluated and the expression `2 + 2` has been parsed, it can then be evaluated to 4, though the value 4 does not itself appear as a literal.
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SDL Abstract Data Types (ADT) support basic data types such as INTEGER, REAL, CHARSTRING as well as structured ones such as structures (STRUCT), enumerated (LITERALS), constants (SYNONYMS). Syntax looks like the one from Pascal, for example an assignment is written ':='.
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Not every type of resource is accessible with NAT64. Protocols that embed IPv4 literal addresses, such as SIP and SDP, FTP, WebSocket, Skype, MSN, and any other content with IPv4 literals are excluded, but a dual-stacked web proxy allows IPv6-only clients to access even web pages with IPv4 literals in URLs. However, 464XLAT (described in RFC 6877), which uses NAT64, allows use of such protocols over IPv6-only connections. For SIP and FTP, the problem can also be solved using an application-level gateway, or using Port Control Protocol with the PREFIX64 extension specified in RFC 7225.
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R does not have file literals, but provides equivalent functionality by combining string literals with a string-to-file function. R allows arbitrary whitespace, including newlines, in strings. A string then can be turned into a file descriptor using the `textConnection()` function. For example, the following turns a data table embedded in the source code into a data-frame variable: str <\- "State Population Income Illiteracy Life.Exp Murder HS.Grad Frost Alabama 3615 3624 2.1 69.05 15.1 41.3 20 Alaska 365 6315 1.5 69.31 11.3 66.7 152 Arizona 2212 4530 1.8 70.55 7.8 58.1 15 Arkansas 2110 3378 1.9 70.66 10.1 39.9 65" x <\- read.
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This clause states one condition under which the statement `A(X,Y)` holds: `X+Y` is greater than zero and both `B(X)` and `C(Y)` are true. As in regular logic programming, programs are queried about the provability of a goal, which may contain constraints in addition to literals. A proof for a goal is composed of clauses whose bodies are satisfiable constraints and literals that can in turn be proved using other clauses. Execution is performed by an interpreter, which starts from the goal and recursively scans the clauses trying to prove the goal.
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Efficiency is strongly affected by the choice of the branching literal: there exist instances for which the running time is constant or exponential depending on the choice of the branching literals. Such choice functions are also called heuristic functions or branching heuristics.
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LEB128 or Little Endian Base 128 is a form of variable-length code compression used to store an arbitrarily large integer in a small number of bytes. LEB128 is used in the DWARF debug file format and the WebAssembly binary encoding for all integer literals.
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For the purposes of these tables, `a`, `b`, and `c` represent valid values (literals, values from variables, or return value), object names, or lvalues, as appropriate. `R`, `S` and `T` stand for any type(s), and `K` for a class type or enumerated type.
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An example of a clause as a disjunction of literals is: ~wealthy(Y) \/ ~smart(Y) \/ ~beautiful(Y) \/ loves(X, Y) where the symbols \/ and ~ are, respectively, OR and NOT. The above example states that if Y is wealthy AND smart AND beautiful then X loves Y. It does not say who X and Y are though. Note that the above representation comes from the logical statement: For all Y, X belonging to the domain of human beings: wealthy(Y) /\ smart(Y) /\ beautiful(Y) => loves(X,Y) By using some transformation rules of formal logic we produce the disjunction of literals of the example given above. X and Y are variables.
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The FOCL algorithmMichael Pazzani and Dennis Kibler. The Utility of Knowledge in Inductive Learning. Machine Learning, Volume 9, Number 1, 1992. (First Order Combined Learner) extends FOIL in a variety of ways, which affect how FOCL selects literals to test while extending a clause under construction.
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This is mainly used to allow the use of variable names that would otherwise conflict with keywords. The same is achieved in VB.Net by enclosing the name in square brackets, as in `[end]`. The "`@`" prefix can also be applied to string literals; see literal affixes below.
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Escape sequences are similar to escape characters, except they usually consist of some kind of mnemonic instead of just a single character. One use is in string literals that include a doublequote (") character. For example in Perl, the code: print "Nancy said \x22Hello World!\x22 to the crowd.
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The term "here document" or "here string" is also used for multiline string literals in various programming languages, notably Perl (syntax influenced by Unix shell), and languages influenced by Perl, notably PHP and Ruby. The shell-style `<<` syntax is often retained, despite not being used for input redirection.
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A 2-satisfiability instance in conjunctive normal form can be transformed into an implication graph by replacing each of its disjunctions by a pair of implications. For example, the statement (x_0\lor x_1) can be rewritten as the pair ( eg x_0 \rightarrow x_1), ( eg x_1 \rightarrow x_0). An instance is satisfiable if and only if no literal and its negation belong to the same strongly connected component of its implication graph; this characterization can be used to solve 2-satisfiability instances in linear time. In CDCL SAT-solvers, unit propagation can be naturally associated with an implication graph that captures all possible ways of deriving all implied literals from decision literals, which is then used for clause learning.
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In other words, after the labeling literal has been considered, all variables are assigned a value. Typically, constraint logic programs are written in such a way labeling literals are evaluated only after as many constraints as possible have been accumulated in the constraint store. This is because labeling literals enforce search, and search is more efficient if there are more constraints to be satisfied. A constraint satisfaction problem is typical solved by a constraint logic program having the following structure: solve(X):-constraints(X), labeling(X) constraints(X):- (all constraints of the CSP) When the interpreter evaluates the goal `solve(args)`, it places the body of a fresh variant of the first clause in the current goal.
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Numeric literals, like the value 500, were converted into their 16-bit (two-byte) binary representation, in this case, $01F4 hexadecimal. To indicate this was a value and not a keyword, a single byte between $B0 and $B9 was inserted in front of the two-byte value. String literals, like "HELLO WORLD" were instead encoded by setting the high bit of each character so that was stored as $C1. Variable names were converted in the same fashion, with the letters encoded to have their high-bit turned on, and any digits in the name represented by the corresponding $B0 through $B9, so that the variable would be encoded as $C1B5 (not reduced to a token).
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This notation can be used for floating-point literals in the C99 edition of the C programming language. Using the %a or %A conversion specifiers, this notation can be produced by implementations of the printf family of functions following the C99 specification and Single Unix Specification (IEEE Std 1003.1) POSIX standard.
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Straight single and double quotation marks are used in most programming languages to delimit strings or literal characters, collectively known as string literals. In some languages (e.g. Pascal) only one type is allowed, in some (e.g. C and its derivatives) both are used with different meanings and in others (e.g.
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In programming, string concatenation generally occurs at run time, as string values are not in general known until run time. However, in the case of string literals, the values are known at compile time, and thus string concatenation can be done at compile time, either via string literal concatenation or via constant folding.
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MIT Press 1988, Given a logical theory relating action occurrences with their effects (for example, a formula of the event calculus), the problem of finding a plan for reaching a state can be modeled as the problem of abducting a set of literals implying that the final state is the goal state.
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JavaScript provides a Boolean data type with and literals. The operator returns the string for these primitive types. When used in a logical context, , , , , , and the empty string () evaluate as due to automatic type coercion. All other values (the complement of the previous list) evaluate as , including the strings , and any object.
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Putting a formula into ANF also makes it easy to identify linear functions (used, for example, in linear feedback shift registers): a linear function is one that is a sum of single literals. Properties of nonlinear feedback shift registers can also be deduced from certain properties of the feedback function in ANF.
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The background knowledge is given as a logic theory , commonly in the form of Horn clauses used in logic programming. The positive and negative examples are given as a conjunction E^+ and E^- of unnegated and negated ground literals, respectively. A correct hypothesis is a logic proposition satisfying the following requirements.; here: Sect.
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A common use of escape sequences is in fact to remove control characters found in a binary data stream so that they will not cause their control function by mistake. In this case, the control character is replaced by a defined "escape character" (which need not be the US-ASCII escape character) and one or more other characters; after exiting the context where the control character would have caused an action, the sequence is recognized and replaced by the removed character. To transmit the "escape character" itself, two copies are sent. In many programming languages and command line interfaces escape sequences are used in character literals and string literals, to express characters which are not printable or clash with the syntax of characters or strings.
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From the C99 standard, C has also supported escape sequences that denote Unicode code points in string literals. Such escape sequences are called universal character names, and have the form or , where stands for a hex digit. Unlike the other escape sequences considered, a universal character name may expand into more than one code unit.
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Many languages provide a built-in string data type, with specialized notation ("string literals") to build values of that type. In some languages (such as C), a string is just an array of characters, or is handled in much the same way. Other languages, like Pascal, may provide vastly different operations for strings and arrays.
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GSS (Graph Style Sheets) is an RDF (Resource Description Framework) vocabulary for representation of data in a model of labeled directed graph. Using it will make a relatively complex data resource modeled in RDF, much easier to understand by declaring simple styling and visibility instructions to be applied on selected resources, literals and properties.
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Fortran compilers using space-squeezing techniques (e.g. IBM 1130)Software: reads the source statements into memory, discards comment lines, removes spaces except in text literals, concatenates continuation lines made it impossible for the compiler to see the problem with: ::::: .... DO 120 J=1 _._ 256 ... 120 CONTINUE :(which is why programs like Lint for FortranLint for Fortran: can be helpful.
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The procedure modifies the tableau in such a way that the formula represented by the resulting tableau is equivalent to the original one. One of these conjunctions may contain a pair of complementary literals, in which case that conjunction is proved to be unsatisfiable. If all conjunctions are proved unsatisfiable, the original set of formulae is unsatisfiable.
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The not operator can only be used as part of a literal, which means that it can only precede a propositional variable or a predicate symbol. In automated theorem proving, the notion "clausal normal form" is often used in a narrower sense, meaning a particular representation of a CNF formula as a set of sets of literals.
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The C# simple types implement several interfaces and consequently offer many methods directly on instances of the types, even on the literals. The C# type names are also merely aliases for Common Language Runtime (CLR) types. The C# `System.Int64` type is exactly the same type as the `long` type; the only difference is that the former is the canonical .
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Espresso-IISOJS is a JavaScript implementation of Espresso-II for single output functions. It employs unit propagation as an additional optimization technique for the various algorithms in Espresso-II that are based on the unate recursive paradigm. Another addition is allowing control over when literals can be raised which can be exploited to effectively minimize Kleene logic functions.
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Golem is an inductive logic programming algorithm developed by Stephen Muggleton and Feng. It uses the technique relative least general generalization proposed by Gordon Plotkin. Therefore, only positive examples are used and the search is bottom-up. Negative examples can be used to reduce the size of the hypothesis by deleting useless literals from the body clause.
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In computing, a here document (here-document, here-text, heredoc, hereis, here-string or here-script) is a file literal or input stream literal: it is a section of a source code file that is treated as if it were a separate file. The term is also used for a form of multiline string literals that use similar syntax, preserving line breaks and other whitespace (including indentation) in the text. Here documents originate in the Unix shell, and are found in the Bourne shell (`sh`), C shell (`csh`), tcsh (`tcsh`), KornShell (`ksh`), Bash, and Z shell (`zsh`), among others. Here document-style string literals are found in various high-level languages, notably the Perl programming language (syntax inspired by Unix shell) and languages influenced by Perl, such as PHP and Ruby.
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Given a goal clause: eg L_1 \lor \cdots \lor eg L_i \lor \cdots \lor eg L_n with selected literal eg L_i , and an input definite clause: L \lor eg K_1 \lor \cdots \lor eg K_m whose positive literal (atom) L\, unifies with the atom L_i \, of the selected literal eg L_i \, , SLD resolution derives another goal clause, in which the selected literal is replaced by the negative literals of the input clause and the unifying substitution \theta \, is applied: ( eg L_1 \lor \cdots \lor eg K_1 \lor \cdots \lor eg K_m\ \lor \cdots \lor eg L_n)\theta In the simplest case, in propositional logic, the atoms L_i \, and L \, are identical, and the unifying substitution \theta \, is vacuous. However, in the more general case, the unifying substitution is necessary to make the two literals identical.
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A literal is either a variable, called positive literal, or the negation of a variable, called negative literal. A clause is a disjunction of literals (or a single literal). A clause is called a Horn clause if it contains at most one positive literal. A formula is in conjunctive normal form (CNF) if it is a conjunction of clauses (or a single clause).
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Variables could also be declared , in which case no local memory was set aside for them and the storage was assumed to be declared in another library. This mirrors the keyword in C. Literals can be specified with various suffixes, and those without a suffix are assumed to be . For instance, would be interpreted as an , while was a . denoted a and a .
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In addition, he and Beauty have also taken over babysitting duties of Bigby and Snow's cubs while the parents were sent to investigate Jack Horner's claims regarding the Literals as well as Rose Red descending heavily into depression following Boy Blue's death. Cole's diplomatic skills later served the Fable community when more Mundies became aware, and thus frightened, of them.
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Integer literals can be made unsigned with `U` suffix. For example, `0x``FFFFFFFF` gives −1, but `0xFFFFFFFFU` gives 4,294,967,295 for 32-bit code. Compilers often issue a warning when comparisons are made between signed and unsigned numbers or when one is cast to the other. These are potentially dangerous operations as the ranges of the signed and unsigned types are different.
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SLDNFKrzysztof Apt and Maarten van Emden, Contributions to the Theory of Logic Programming, Journal of the Association for Computing Machinery. Vol, 1982 - portal.acm.org is an extension of SLD resolution to deal with negation as failure. In SLDNF, goal clauses can contain negation as failure literals, say of the form not(p) \, , which can be selected only if they contain no variables.
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Building upon previous work on the PCP theorem, Johan Håstad showed that, assuming P ≠ NP, no polynomial-time algorithm for MAX 3SAT can achieve a performance ratio exceeding 7/8, even when restricted to satisfiable instances of the problem in which each clause contains exactly three literals. Both the Karloff–Zwick algorithm and the above simple algorithm are therefore optimal in this sense..
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In the maximum-2-satisfiability problem (MAX-2-SAT), the input is a formula in conjunctive normal form with two literals per clause, and the task is to determine the maximum number of clauses that can be simultaneously satisfied by an assignment. Like the more general maximum satisfiability problem, MAX-2-SAT is NP-hard. The proof is by reduction from 3SAT.; see pp.
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Apple introduced blocks, a form of closure, as a nonstandard extension into C, C++, Objective-C 2.0 and in Mac OS X 10.6 "Snow Leopard" and iOS 4.0. Apple made their implementation available for the GCC and clang compilers. Pointers to block and block literals are marked with `^`. Normal local variables are captured by value when the block is created, and are read-only inside the block.
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To support this English-like syntax, COBOL has over 300 keywords. Some of the keywords are simple alternative or pluralized spellings of the same word, which provides for more English-like statements and clauses; e.g., the and keywords can be used interchangeably, as can and , and and . Each COBOL program is made up of four basic lexical items: words, literals, picture character-strings (see ) and separators.
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SQL Server 2005 (formerly codenamed "Yukon") released in November 2005. It included native support for managing XML data, in addition to relational data. For this purpose, it defined an `xml` data type that could be used either as a data type in database columns or as literals in queries. XML columns can be associated with XSD schemas; XML data being stored is verified against the schema.
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Though JSON was originally advertised and believed to be a strict subset of JavaScript and ECMAScript, it inadvertently allowed some unescaped characters in strings that were illegal in JavaScript and ECMAScript string literals. JSON became a strict subset of ECMAScript as of the language's 2019 revision. See Data portability issues below. In October 2013, Ecma International published the first edition of its JSON standard ECMA-404.
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The Ignition Expression Language is a simple language that was invented by Inductive Automation. An expression language is a very simple kind of language where everything is an expression - which is a piece of code that returns a value. This means that there are no statements and no variables, just operators, literals, and functions. Consider an example from the expression language found in Microsoft_excel.
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Other languages often use substantially similar syntax, but details of syntax and actual functionality can vary significantly. When used simply for string literals, the `<<` does not indicate indirection, but is simply a starting delimiter convention. In some languages, such as Ruby, `<<` is also used for input redirection, thus resulting in `<<` being used twice if one wishes to redirect from a here document string literal.
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Constraint logic programming is a form of constraint programming, in which logic programming is extended to include concepts from constraint satisfaction. A constraint logic program is a logic program that contains constraints in the body of clauses. An example of a clause including a constraint is . In this clause, is a constraint; `A(X,Y)`, `B(X)`, and `C(Y)` are literals as in regular logic programming.
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Rust uses a variant of the `r` prefix:raw byte string literals at rust-lang.org. "\x52"; // R r"\x52"; // \x52 r#""foo""#; // "foo" r##"foo #"# bar"##; // foo #"# bar The literal starts with `r` followed by any number of `#`, followed by one `"`. Further `"` contained in the literal are considered part of the literal, unless followed by at least as many `#` as used after the opening `r`.
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If an unsatisfied clause has all but one of its literals or variables evaluated at False, then the free literal must be True in order for the clause to be True. For example, if the below unsatisfied clause is evaluated with A = False and B = False we must have C = True in order for the clause (A \lor B \lor C ) to be true.
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Implicit string concatenation is not required by modern compilers, which implement constant folding, and causes hard-to-spot errors due to unintentional concatenation from omitting a comma, particularly in vertical lists of strings, as in: l = ['foo', 'bar' 'zork'] Accordingly, it is not used in most languages, and it has been proposed for deprecation from DDLang's Issue Tracking System – Issue 3827 - Warn against and then deprecate implicit concatenation of adjacent string literals and Python. However, removing the feature breaks backwards compatibility, and replacing it with a concatenation operator introduces issues of precedence – string literal concatenation occurs during lexing, prior to operator evaluation, but concatenation via an explicit operator occurs at the same time as other operators, hence precedence is an issue, potentially requiring parentheses to ensure desired evaluation order. A subtler issue is that in C and C++,C++11 draft standard, , 2.14.5 String literals [lex.
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A truth table for a Boolean function of n variables has exactly 2^n rows, the inputs of each row corresponding naturally to a minterm whose context is the set of independent variables of that Boolean function. (Each 0-input corresponds to a negated variable; each 1-input corresponds to an asserted variable.) Any Boolean expression may be converted to sum-of-minterms form by repeatedly distributing AND with respect to OR, NOT with respect to AND or OR (through the De Morgan identities), cancelling out double negations (cf. negation normal form); and then, when a sum-of-products has been obtained, multiply products with missing literals with instances of the law of excluded middle that contain the missing literals; then — lastly — distribute AND with respect to OR again. Note that there is a formal correspondence, for a given context, between Zhegalkin monomials and Boolean minterms.
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There are also 15 other ways of setting all the variables so that the formula becomes true. Therefore, the 2-satisfiability instance represented by this expression is satisfiable. Formulas in this form are known as 2-CNF formulas. The "2" in this name stands for the number of literals per clause, and "CNF" stands for conjunctive normal form, a type of Boolean expression in the form of a conjunction of disjunctions.
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The resolution rule, as defined by Robinson, also incorporated factoring, which unifies two literals in the same clause, before or during the application of resolution as defined above. The resulting inference rule is refutation-complete, p. 350 (= p. 286 in the 1st edition of 1995) in that a set of clauses is unsatisfiable if and only if there exists a derivation of the empty clause using only resolution, enhanced by factoring.
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Highlighting the effect of missing delimiter (after watch='false) in JavaScript Syntax highlighting is one strategy to improve the readability and context of the text; especially for code that spans several pages. The reader can easily ignore large sections of comments or code, depending on what they are looking for. Syntax highlighting also helps programmers find errors in their program. For example, most editors highlight string literals in a different color.
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This is almost the same as the plain quote, except it allows expressions to be evaluated and their values interpolated into a quoted list with the comma unquote and comma-at splice operators. If the variable has the value then evaluates to , while evaluates to . The backquote is most often used in defining macro expansions.Quasiquotation in Lisp , Alan Bawden Self-evaluating forms and quoted forms are Lisp's equivalent of literals.
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P2 will choose an unsatisfying clause to win. Then when it is P1's turn he must choose a literal in that clause chosen by P2. Since all the literals in the clause are false, they do not connect to previously visited nodes in the left vertical chain. This allows P2 to follow the connection to the corresponding node in a diamond of the left chain and select it.
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On the other hand, in the second formulation the search is performed only when the constraint is already in the constraint store. As a result, search only returns solutions that are consistent with it, taking advantage of the fact that additional constraints reduce the search space. A second reformulation that can increase efficiency is to place constraints before literals in the body of clauses. Again, and are in principle equivalent.
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The quoted-printable encoding uses the equals sign as an escape character. URL and URI use %-escapes to quote characters with a special meaning, as for non- ASCII characters. The ampersand () character may be considered as an escape character in SGML and derived formats such as HTML and XML. Some programming languages also provide other ways to represent special characters in literals, without requiring an escape character (see e.g.
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Having been able to break in a new pen, after destroying the pen (a simple goose-feather) used to write the Fables (and possibly the mundys as well) in the attempt to stop the Writer's Block, he becomes displeased with the current events, as the Fables themselves had grown beyond his control (he explicitly claims that Geppetto's transformation in the dreaded Adversary was something he couldn't even fathom), and decided to uncreate them, rebuilding a new world from scratch. After Jack Frost II is able to stop him from writing the literal word end to the universe, Dex, the Deus Ex Machina and the most powerful of the Literals, creates a new, empty universe for the Literals to inhabit and fill out as they please. Despite having a new occasion to create, Kevin expresses displeasure and worries, as after thousands of years spent dreaming the end of the universe, he's unable to write out a beginning to a new universe.
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Plan of HoltunKovacevich and Cardona, Eds. 2014 Holtun has been mapped three times since the first reconnaissance in 1994. The first version of the map was created in 1994 as part of the first approaching to the site.Ponciano 1995: 491 The first survey reported 86 structures which were organized in four groups named with the literals A, B, C and D. The second map was created by the "Proyecto de Sitios Arqueológicos de Petén" (PROSIAPETEN).
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In SL resolution, the selected literal is restricted to one which has been most recently introduced into the clause. In the simplest case, such a last-in-first-out selection function can be specified by the order in which literals are written, as in Prolog. However, the selection function in SLD resolution is more general than in SL resolution and in Prolog. There is no restriction on the literal that can be selected.
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Some languages provide more than one kind of literal, which have different behavior. This is particularly used to indicate raw strings (no escaping), or to disable or enable variable interpolation, but has other uses, such as distinguishing character sets. Most often this is done by changing the quoting character or adding a prefix or suffix. This is comparable to prefixes and suffixes to integer literals, such as to indicate hexadecimal numbers or long integers.
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This notation is particularly well known due to its use in Perl, where it forms part of the syntax distinct from normal string literals. In some cases, such as sed and Perl, alternative delimiters can be used to avoid collision with contents, and to avoid having to escape occurrences of the delimiter character in the contents. For example, in sed the command `s,/,X,` will replace a `/` with an `X`, using commas as delimiters.
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In some cases the same syntax can be used for distinct purposes, which can cause confusion. For example, in C#, the "`@`" prefix can be used either for stropping (to allow reserved words to be used as identifiers), or as a prefix to a literal (to indicate a raw string); in this case neither use is a sigil, as it affects the syntax of identifiers or the semantics of literals, not the semantics of identifiers.
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Finite automata are often used in the frontend of programming language compilers. Such a frontend may comprise several finite-state machines that implement a lexical analyzer and a parser. Starting from a sequence of characters, the lexical analyzer builds a sequence of language tokens (such as reserved words, literals, and identifiers) from which the parser builds a syntax tree. The lexical analyzer and the parser handle the regular and context-free parts of the programming language's grammar.
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Zstandard combines a dictionary-matching stage (LZ77) with a large search window and a fast entropy coding stage, using both Finite State Entropy (a fast tabled version of ANS, tANS, used for entries in the Sequences section), and Huffman coding (used for entries in the Literals section). Because of the way that FSE carries over state between symbols, decompression involves processing symbols within the Sequences section of each block in reverse order (from last to first).
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Empire-db's key strength is its API for dynamic SQL generation for arbitrary select, update, insert or delete statements, purely by using Java methods which reference the model objects. This provides type-safety and almost entirely eliminates the use of string literals for names or expressions in code. Additionally DBMS independence is achieved through a pluggable driver model. Using references to table and column objects significantly improves compile-time safety and thus reduces the amount of testing.
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Next to 2-satisfiability, the other major subclass of satisfiability problems that can be solved in polynomial time is Horn-satisfiability. In this class of satisfiability problems, the input is again a formula in conjunctive normal form. It can have arbitrarily many literals per clause but at most one positive literal. found a generalization of this class, renamable Horn satisfiability, that can still be solved in polynomial time by means of an auxiliary 2-satisfiability instance.
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See Algorithms for solving SAT below. SAT is trivial if the formulas are restricted to those in disjunctive normal form, that is, they are disjunction of conjunctions of literals. Such a formula is indeed satisfiable if and only if at least one of its conjunctions is satisfiable, and a conjunction is satisfiable if and only if it does not contain both x and NOT x for some variable x. This can be checked in linear time.
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The Fables soon found out about his deed and they sent out the town sheriff Beast to apprehend him for his crime. Unfortunately for Jack, Beast managed to find him in Hollywood, confiscated all the money and properties he had built, and was told that he can never set foot on Fabletown again. The series then starts off after Jack left Hollywood. While hitchhiking, Jack was captured by an armed group of magical creatures calling themselves Literals.
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These constants differ from literals in a number of ways. Compilers generally place a constant in a single memory location identified by symbol, rather than spread throughout the executable as with a macro. While this precludes the speed advantages of immediate mode, there are advantages in memory efficiency, and debuggers can work with these constants at runtime. Also while macros may be redefined accidentally by conflicting header files in C and C++, conflicting constants are detected at compile time.
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Rules, and even disjunctive rules, have a rather special syntactic form, in comparison with arbitrary propositional formulas. Each disjunctive rule is essentially an implication such that its antecedent (the body of the rule) is a conjunction of literals, and its consequent (head) is a disjunction of atoms. David Pearce [1997] and Paolo Ferraris [2005] showed how to extend the definition of a stable model to sets of arbitrary propositional formulas. This generalization has applications to answer set programming.
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Many more of the control codes have been given meanings quite different from their original ones. The "escape" character (ESC, code 27), for example, was intended originally to allow sending other control characters as literals instead of invoking their meaning. This is the same meaning of "escape" encountered in URL encodings, C language strings, and other systems where certain characters have a reserved meaning. Over time this meaning has been co-opted and has eventually been changed.
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Because `IIf` is a library function, it will always require the overhead of a function call, whereas a conditional operator will more likely produce inline code. Furthermore, the data type of its arguments is `Variant`. If the function is called with arguments of other types (variables or literals), there will be additional overhead to convert these to `Variant`. There may also be additional overhead to check the argument types and convert one of them if they do not have the same type.
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The TLS implementation has also been updated to support extensions as outlined in RFC 3546, most notable of which is Server Name Indication support. Internet Explorer 7 additionally features an update to the WinInet API. The new version has better support for IPv6, and handles hexadecimal literals in the IPv6 address. It also includes better support for Gzip and deflate compression, so that communication with a web server can be compressed and thus will require less data to be transferred.
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Pearson always claimed that he formulated the architecture of CADES while studying Koestler's book on a beach in Tunisia. Arranged in a hierarchy, holons provide a 'family tree' (for each sub-system), utilising parent/child relationships. Holons also maintained attributes of interaction, enabling one Holon to interact with other Holons, thus enabling more modular development and facilitating reuse. In a similar fashion CADES also retained information with regard to constant values (aka literals), user-defined types and user- defined structures.
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A common data structure used to implement symbol tables is the hash table. The time for searching in hash tables is independent of the number of elements stored in the table, so it is efficient for a large number of elements. It also simplifies the classification of literals in tabular format. As the lexical analyser spends a great proportion of its time looking up the symbol table, this activity has a crucial effect on the overall speed of the compiler.
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CADES is not merely a version control system for code modules: it manages all aspects of the software lifecycle from requirements capture, design methodology and specification through to field maintenance. CADES was used in VME module development to hold separate definitions of data structures (Modes), constants (Literals), procedural interfaces and the core algorithms. Multiple versions ('Lives') of each of these components could exist. The algorithms were written in System Development Language (SDL), which was then converted to S3 source by a pre-processor.
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Some languages, such as Perl, PHP, and many shell languages, treat single quoted strings as "raw" strings, while double quoted strings have expressions (such as `"$variable"`) replaced with their values when interpreted. The C programming language (and many derived languages like C++, Java, C#, and Scala) uses apostrophes to delimit a character literal. In these languages a character is a different object than a one-letter string. In C++, since C++14, apostrophes are also used as digit separators in numeric literals.
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Some interpreted languages offer a similar facility to the data segment, notably Perlperldata: Special Literals and Ruby.Ruby: Object: __END__ In these languages, including the line `__DATA__` (Perl) or `__END__` (Ruby, old Perl) marks the end of the code segment and the start of the data segment. Only the contents prior to this line are executed, and the contents of the source file after this line are available as a file object: `PACKAGE::DATA` in Perl (e.g., `main::DATA`) and `DATA` in Ruby.
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In the programming language Lisp, the reader or `read` function is the parser which converts the textual form of Lisp objects to the corresponding internal object structure. In the original Lisp, S-expressions consisted only of symbols, integers, and the list constructors `( xi... )` and `(x . y)`. Later Lisps, culminating in Common Lisp, added literals for floating-point, complex, and rational numbers, strings, and constructors for vectors. The reader is responsible for parsing list structure, interning symbols, converting numbers to internal form, and calling read macros.
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GeoSPARQL is a standard developed by the Ordnance Survey, United States Geological Survey, Natural Resources Canada, Australia's Commonwealth Scientific and Industrial Research Organisation and others to support ontology creation and reasoning using well-understood OGC literals (GML, WKT), topological relationships (Simple Features, RCC8, DE-9IM), RDF and the SPARQL database query protocols. Recent research results in this area can be seen in the International Conference on Geospatial Semantics and the Terra Cognita – Directions to the Geospatial Semantic Web workshop at the International Semantic Web Conference.
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Mr. Revise is in overall charge of the Golden Boughs Retirement Village. His exact status is unclear, but he is descended from Literals, a group of magical beings who, unlike the Fables, who are characters from story, appear to personify literary concepts. He seems to embody the concept of the editor, in that he revises the universe so that it makes perfect sense. He is the son of Kevin Thorn and the grandson of the Pathetic Fallacy, though he appears older than both of them.
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Since the formula represented by a tableau is the disjunction of the formulae represented by its branches, contradiction is obtained when every branch contains a pair of opposite literals. Once a branch contains a literal and its negation, its corresponding formula is unsatisfiable. As a result, this branch can be now "closed", as there is no need to further expand it. If all branches of a tableau are closed, the formula represented by the tableau is unsatisfiable; therefore, the original set is unsatisfiable as well.
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Dynamic-link libraries (DLLs) in Microsoft Windows use variant E8 of the CALL instruction (Call near, relative, displacement relative to next instruction). These instructions need not be fixed up when a DLL is loaded. Some global variables (e.g. arrays of string literals, virtual function tables) are expected to contain an address of an object in data section respectively in code section of the dynamic library; therefore, the stored address in the global variable must be updated to reflect the address where the DLL was loaded to.
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Perlperldata: Special Literals and RubyRuby: Object: __END__ have a form of file literal, which can be considered a form of data segment. In these languages, including the line `__DATA__` (Perl) or `__END__` (Ruby, old Perl) marks the end of the code segment and the start of the data segment. Only the contents prior to this line are executed, and the contents of the source file after this line are available as a file object: `PACKAGE::DATA` in Perl (e.g., `main::DATA`) and `DATA` in Ruby.
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The current domain of a variable can be inspected using specific literals; for example, `dom(X,D)` finds out the current domain `D` of a variable `X`. As for domains of reals, functors can be used with domains of integers. In this case, a term can be an expression over integers, a constant, or the application of a functor over other terms. A variable can take an arbitrary term as a value, if its domain has not been specified to be a set of integers or constants.
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C# has a unified type system in which all types (besides unsafe pointers) ultimately derive from a common root type. Consequently, all types implement the methods of this root type, and extension methods defined for the `object` type apply to all types, even primitive `int` literals and delegates. This allows C#, unlike Java, to support objects with encapsulation that are not reference types. In Java, compound types are synonymous with reference types; methods cannot be defined for a type unless it is also a class reference type.
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A Tigrinya verb root consists of a set of consonants (or "literals"), usually three, for example, {sbr} 'break' (citation form: ሰበረ säbärä), {drf} 'sing' (citation form: ደረፈ däräfä). Each three-consonant (or "triliteral") root belongs to one of three conjugation classes, conventionally known as A, B, and C, and analogous to the three conjugations of verbs in Romance languages. This division is a basic feature of Ethiopian Semitic languages. Most three- consonant roots are in the A class (referred to in this article as "3A").
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This was the official language of the deterministic track of the 4th IPC in 2004. It introduced derived predicates (to model the dependency of given facts from other facts, e.g. if A is reachable from B, and B is reachable from C, then A is reachable from C (transitivity)), and timed initial literals (to model exogenous events occurring at given time independently from plan-execution). Eventually PDDL2.2 extended the language with a few important elements, but wasn't a radical evolution compared to PDDL2.1 after PDDL1.2.
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Languages differ on whether and how to interpret string literals as either 'raw' or 'variable interpolated'. Variable interpolation is the process of evaluating an expression containing one or more variables, and returning output where the variables are replaced with their corresponding values in memory. In sh- compatible Unix shells (as well as Perl and Ruby), quotation-delimited (") strings are interpolated, while apostrophe-delimited (') strings are not. For example, the following Perl code: $name = "Nancy"; $greeting = "Hello World"; print "$name said $greeting to the crowd of people.
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Logical disjunction is an operation on two logical values, typically the values of two propositions, that has a value of false if and only if both of its operands are false. More generally, a disjunction is a logical formula that can have one or more literals separated only by 'or's. A single literal is often considered to be a degenerate disjunction. The disjunctive identity is false, which is to say that the or of an expression with false has the same value as the original expression.
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A common alternative to is to use a variable-width encoding, whereby a logical character may extend over multiple positions of the string. Variable-width strings may be encoded into literals verbatim, at the risk of confusing the compiler, or using numerical backslash escapes (e.g. for "é" in UTF-8). The UTF-8 encoding was specifically designed (under Plan 9) for compatibility with the standard library string functions; supporting features of the encoding include a lack of embedded nulls, no valid interpretations for subsequences, and trivial resynchronisation.
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Attributes may be of primitive type (numeric, string, boolean), enum type or node type. Attributes are used to store literals during tree construction and additional information gathered during tree analysis (for example, links between reference and definition, to represent higher-order abstract syntax). Operations over a tree are defined as multimethods. Advantages of this approach are described in the article Treecc: An Aspect-Oriented Approach to Writing Compilers Tree descriptions support inheritance to allow modularity and reuse of base language tree descriptions for language extensions.
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Internet Explorer 7 adds support for per-pixel alpha transparency in PNG,IE7 Transparent PNG Implementation, IEBlog as well as minor improvements to HTML, CSS and DOM support. Microsoft's stated goal with version 7 was to fix the most significant bugs and areas which caused the most trouble for developers, however full compatibility with standards was postponed. Internet Explorer 7 additionally features an update to the WinInet API. The new version has better support for IPv6, and handles hexadecimal literals in the IPv6 address.
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The pseudocode DPLL function only returns whether the final assignment satisfies the formula or not. In a real implementation, the partial satisfying assignment typically is also returned on success; this can be derived from the consistent set of literals of the first `if` statement of the function. The Davis–Logemann–Loveland algorithm depends on the choice of branching literal, which is the literal considered in the backtracking step. As a result, this is not exactly an algorithm, but rather a family of algorithms, one for each possible way of choosing the branching literal.
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In the 2010s years, work on improving the algorithm has been done on three directions: # Defining different policies for choosing the branching literals. # Defining new data structures to make the algorithm faster, especially the part on unit propagation # Defining variants of the basic backtracking algorithm. The latter direction include non-chronological backtracking (aka backjumping) and clause learning. These refinements describe a method of backtracking after reaching a conflict clause which "learns" the root causes (assignments to variables) of the conflict in order to avoid reaching the same conflict again.
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A small pre-calculated CNF expression that relates the inputs and outputs is appended (via the "and" operation) to the output expression. Note that inputs to these gates can be either the original literals or the introduced variables representing outputs of sub- gates. Though the output expression contains more variables than the input, it remains equisatisfiable, meaning that it is satisfiable if, and only if, the original input equation is satisfiable. When a satisfying assignment of variables is found, those assignments for the introduced variables can simply be discarded.
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In computer science, a literal is a notation for representing a fixed value in source code. Almost all programming languages have notations for atomic values such as integers, floating-point numbers, and strings, and usually for booleans and characters; some also have notations for elements of enumerated types and compound values such as arrays, records, and objects. An anonymous function is a literal for the function type. In contrast to literals, variables or constants are symbols that can take on one of a class of fixed values, the constant being constrained not to change.
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For example, is a single octal escape sequence denoting a byte with numerical value 9 (11 in octal), rather than the escape sequence followed by the digit . However, is the octal escape sequence followed by the digit . In order to denote the byte with numerical value 1, followed by the digit , one could use , since C automatically concatenates adjacent string literals. Note that some three-digit octal escape sequences may be too large to fit in a single byte; this results in an implementation- defined value for the byte actually produced.
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Some tokens such as parentheses do not really have values, and so the evaluator function for these can return nothing: only the type is needed. Similarly, sometimes evaluators can suppress a lexeme entirely, concealing it from the parser, which is useful for whitespace and comments. The evaluators for identifiers are usually simple (literally representing the identifier), but may include some unstropping. The evaluators for integer literals may pass the string on (deferring evaluation to the semantic analysis phase), or may perform evaluation themselves, which can be involved for different bases or floating point numbers.
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SUPER BASIC allowed string constants (literals) to be enclosed with single or double quotes, so and were both valid statements. In contrast to later dialects of BASIC, one could assign a string to any variable and the signifier was not used, so was valid. This could lead to some confusion when a user provided a value combining digits and letters, and SUPER BASIC assumed anything starting with a digit was a number. To guide the system when this might result in confusing input, one could explicitly declare string variables using .
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But there is no TIMESTAMP type that can contain fine-grained timestamp up to millisecond or nanosecond. Oracle Datatypes The `TO_DATE` function can be used to convert strings to date values. The function converts the first quoted string into a date, using as a definition the second quoted string, for example: to_date('31-12-2004', 'dd- mm-yyyy') or to_date ('31-Dec-2004', 'dd-mon-yyyy', 'NLS_DATE_LANGUAGE = American') To convert the dates to strings one uses the function `TO_CHAR (date_string, format_string)`. PL/SQL also supports the use of ANSI date and interval literals.
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Factor's syntax is often extended to allow for new types of word definitions and new types of literals for data structures. It is also used in the XML library to provide literal syntax for generating XML. For example, the following word takes a string and produces an XML document object which is an HTML document emphasizing the string: : make-html ( string -- xml ) dup # <-> XML> ; The word `dup` duplicates the top item on the stack. The `<->` stands for filling in that part of the XML document with an item from the stack.
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Formally, constraint logic programs are like regular logic programs, but the body of clauses can contain constraints, in addition to the regular logic programming literals. As an example, `X>0` is a constraint, and is included in the last clause of the following constraint logic program. B(X,1):- X<0\. B(X,Y):- X=1, Y>0. A(X,Y):- X>0, B(X,Y). Like in regular logic programming, evaluating a goal such as `A(X,1)` requires evaluating the body of the last clause with `Y=1`.
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"x loves y", the formula reads "If everybody loves somebody, then a single person must exist that is loved by everyone." (\forall x \exists y. p(x,y)) \rightarrow (\exists y \forall x. p(x,y)): the negation of that formula has the conjunctive normal form p(X,f(X)) \land \lnot p(g(Y),Y), with f and g denoting the Skolem function for the first and second existential quantifier, respectively; the literals p(X,f(X)) and p(g(Y),Y) are unifiable without occurs check, producing the refuting empty clause.
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The null character is often represented as the escape sequence `\0` in source code string literals or character constants.Kernighan and Ritchie, C, p. 38 In many languages (such as C, which introduced this notation), this is not a separate escape sequence, but an octal escape sequence with a single octal digit 0; as a consequence, `\0` must not be followed by any of the digits `0` through `7`; otherwise it is interpreted as the start of a longer octal escape sequence.In YAML this combination is a separate escape sequence.
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In object-oriented programming, there is also the concept of a static member variable, which is a "class variable" of a statically defined class, i.e., a member variable of a given class which is shared across all instances (objects), and is accessible as a member variable of these objects. A class variable of a dynamically defined class, in languages where classes can be defined at run time, is allocated when the class is defined and is not static. Object constants known at compile-time, such as string literals, are usually allocated statically.
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A few languages provide a method of specifying that a literal is to be processed without any language- specific interpretation. This avoids the need for escaping, and yields more legible strings. Raw strings are particularly useful when a common character needs to be escaped, notably in regular expressions (nested as string literals), where backslash `\` is widely used, and in DOS/Windows paths, where backslash is used as a path separator. The profusion of backslashes is known as leaning toothpick syndrome, and can be reduced by using raw strings.
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For external use by computer specialists, this binary representation is sometimes presented in the related octal or hexadecimal systems. For most purposes, however, binary values are converted to or from the equivalent decimal values for presentation to or input from humans; computer programs express literals in decimal by default. (123.1, for example, is written as such in a computer program, even though many computer languages are unable to encode that number precisely.) Both computer hardware and software also use internal representations which are effectively decimal for storing decimal values and doing arithmetic.
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The satisfiability problem consists in finding a satisfying assignment for a given formula in conjunctive normal form (CNF). An example of such a formula is: :( (not A) or (not C) ) and (B or C), or, using a common notation:In the pictures below, "+" is used to denote "or", and multiplcation to denote "and". :(A' \lor C') \land (B \lor C) where A,B,C are Boolean variables, A', C', B, and C are literals, and A' \lor C' and B \lor C are clauses. A satisfying assignment for this formula is e.g.
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Consequently, simply typed lambda calculus extended with record types is perhaps the simplest theoretical setting in which a useful notion of subtyping may be defined and studied . Because the resulting calculus allows terms to have more than one type, it is no longer a "simple" type theory. Since functional programming languages, by definition, support function literals, which can also be stored in records, records types with subtyping provide some of the features of object-oriented programming. Typically, functional programming languages also provide some, usually restricted, form of parametric polymorphism.
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A character literal is a type of literal in programming for the representation of a single character's value within the source code of a computer program. Languages that have a dedicated character data type generally include character literals; these include C, C++, Java, and Visual Basic. Languages without character data types (like Python or PHP) will typically use strings of length 1 to serve the same purpose a character data type would fulfil. This simplifies the implementation and basic usage of a language but also introduces new scope for programming errors.
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Algebraic Logic Functional programming language, also known as ALF, is a programming language which combines functional and logic programming techniques. Its foundation is Horn clause logic with equality which consists of predicates and Horn clauses for logic programming, and functions and equations for functional programming. ALF was designed to be genuine integration of both programming paradigms, and thus any functional expression can be used in a goal literal and arbitrary predicates can occur in conditions of equations. ALF's operational semantics is based on the resolution rule to solve literals and narrowing to evaluate functional expressions.
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String literals (constants) were entered between double-quotes. Characters within strings could be escaped by placing their ASCII value between angle-brakets, for instance, String variables, like their numeric counterparts, consisted of only a single letter, or one letter and one digit. As is the case for all variables in Extended BASIC, string variables were normally allocated ten spaces, but could be extended up to a maximum of 32 k with an explicit . Because the array syntax was used to declare the length of the string, string arrays were not possible.
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Truncating strings with variable length characters using functions like `strncpy` can produce invalid sequences at the end of the string. This can be unsafe if the truncated parts are interpreted by code that assumes the input is valid. Support for Unicode literals such as `char foo[512] = "φωωβαρ";`(UTF-8) or `wchar_t foo[512] = L"φωωβαρ";` (UTF-16 or UTF-32, depends on ) is implementation defined, and may require that the source code be in the same encoding, especially for where compilers might just copy whatever is between the quotes.
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The ISO SQL:1999 standard introduced the BOOLEAN data type to SQL, however it's still just an optional, non-core feature, coded T031. When restricted by a `NOT NULL` constraint, the SQL BOOLEAN works like the Boolean type from other languages. Unrestricted however, the BOOLEAN datatype, despite its name, can hold the truth values TRUE, FALSE, and UNKNOWN, all of which are defined as boolean literals according to the standard. The standard also asserts that NULL and UNKNOWN "may be used interchangeably to mean exactly the same thing".
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The exponential time hypothesis (ETH) is that 3SAT, the satisfiability problem of Boolean formulas in conjunctive normal form with, at most, three literals per clause and with n variables, cannot be solved in time 2o(n). More precisely, the hypothesis is that there is some absolute constant such that 3SAT cannot be decided in time 2cn by any deterministic Turing machine. With m denoting the number of clauses, ETH is equivalent to the hypothesis that kSAT cannot be solved in time 2o(m) for any integer . The exponential time hypothesis implies P ≠ NP.
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The simple Sethi–Ullman algorithm works as follows (for a load/store architecture): # Traverse the abstract syntax tree in pre- or postorder ## For every non-constant leaf node, assign a 1 (i.e. 1 register is needed to hold the variable/field/etc.) if it is the left child of its parent else assign a 0. For every constant leaf node (RHS of an operation – literals, values), assign a 0. ## For every non-leaf node n, assign the number of registers needed to evaluate the respective subtrees of n.
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The Golden Boughs resembles the Village of The Prisoner in some ways, and as he escapes from the Golden Boughs, Jack Horner explicitly makes the connection in a narrative aside to the reader about the place "in the British TV show" guarded by the evil "weather balloon." After the Bookburner's strike on the Golden Boughs, Jack, his fellow Fables, the Literals and the librarians were forced to release Wy'east Klickitat and Loo-With, Native American mountain spirits who unleashed a roaring volcano upon escape, marking the end of the Golden Boughs Retirement Village.
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Each SKOS `label` is a string of Unicode characters, optionally with language tags, that are associated with a concept. The `prefLabel` is the preferred human-readable string (maximum one per language tag), while `altLabel` can be used for alternative strings, and `hiddenLabel` can be used for strings that are useful to associate, but not meant for humans to read. A SKOS `notation` is similar to a label, but the literal string has a datatype, like integer, float, or date; the datatype can even be made up (see 6.5.1 Notations, Typed Literals and Datatypes in the SKOS Reference).
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A compiler usually has two distinct components. A lexical analyzer, sometimes generated by a tool like `lex`, identifies the tokens of the programming language grammar, e.g. identifiers or keywords, numeric and string literals, punctuation and operator symbols, which are themselves specified by a simpler formal language, usually by means of regular expressions. At the most basic conceptual level, a parser, sometimes generated by a parser generator like `yacc`, attempts to decide if the source program is syntactically valid, that is if it is well formed with respect to the programming language grammar for which the compiler was built.
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Semantic Web Conference (ISWC 2011), 2011. in Linked Data published on the Web, out of the 783 domains contributing to the corpus, 345 (44.1%) did not publish any blank nodes. The average percentage of unique terms which were blank nodes for each domain was 7.5%, indicating that although a small number of high-volume domains publish many blank nodes, many other domains publish blank nodes more infrequently. From the 286.3 MB unique terms found in data-level positions the 165.4 MB (57.8%) were blank nodes, 92.1 MB (32.2%) were URIs, and 28.9 MB (10%) were literals.
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The IETF recommends that if a protocol either (a) always uses UTF-8, or (b) has some other way to indicate what encoding is being used, then it "SHOULD forbid use of U+FEFF as a signature." Not using a BOM allows text to be backwards-compatible with some software that is not Unicode-aware. Examples include programming languages that permit non-ASCII bytes in string literals but not at the start of the file. UTF-8 is a sparse encoding in the sense that a large fraction of possible byte combinations do not result in valid UTF-8 text.
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The 3-SAT instance (x ∨ x ∨ y) ∧ (¬x ∨ ¬y ∨ ¬y) ∧ (¬x ∨ y ∨ y) reduced to a clique problem. The green vertices form a 3-clique and correspond to the satisfying assignment x=FALSE, y=TRUE. Like the satisfiability problem for arbitrary formulas, determining the satisfiability of a formula in conjunctive normal form where each clause is limited to at most three literals is NP-complete also; this problem is called 3-SAT, 3CNFSAT, or 3-satisfiability. To reduce the unrestricted SAT problem to 3-SAT, transform each clause to a conjunction of n − 2 clauses : : : : : where are fresh variables not occurring elsewhere.
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The size of the search tree depends on the number of (children) tableaux that can be generated from a given (parent) one. Reducing the number of such tableaux therefore reduces the required search. A way for reducing this number is to disallow the generation of some tableaux based on their internal structure. An example is the condition of regularity: if a branch contains a literal, using an expansion rule that generates the same literal is useless because the branch containing two copies of the literals would have the same set of formulae of the original one.
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However, the formulae in this branch are exactly the same as the formulae of B alone. As a result, the same expansion steps that close B - L also close B. This means that expanding C was unnecessary; moreover, if C contained other literals, its expansion generated other leaves that needed to be closed. In the propositional case, the expansion needed to close these leaves are completely useless; in the first-order case, they may only affect the rest of the tableau because of some unifications; these can however be combined to the substitutions used to close the rest of the tableau.
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Vertigo's Fables line had its first crossover, The Great Fables Crossover, a nine-issue storyline, through its two ongoing titles plus a limited series, The Literals in 2009. In June 2009, Vertigo launched its first line in Vertigo Crime with Filthy Rich, followed by Dark Entries, both as black and white hardcovers. On July 23, 2010, Karen Berger announced DC universe characters would return to the DC imprint, thus canceling a title and effecting a proposed new Swamp Thing series. In 2010, Vertigo saw another Fables spin-off, Cinderella: From Fabletown With Love and its 100-page "Spectacular" reprints program began.
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The labeling literals are used on variables over finite domains to check satisfiability or partial satisfiability of the constraint store and to find a satisfying assignment. A labeling literal is of the form `labeling([variables])`, where the argument is a list of variables over finite domains. Whenever the interpreter evaluates such a literal, it performs a search over the domains of the variables of the list to find an assignment that satisfies all relevant constraints. Typically, this is done by a form of backtracking: variables are evaluated in order, trying all possible values for each of them, and backtracking when inconsistency is detected.
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The only exception is the primitive types, which are not represented by a class instance for performance reasons (though can be automatically converted to objects and vice versa via autoboxing). Some features like operator overloading or unsigned integer types are omitted to simplify the language and to avoid possible programming mistakes. The Java syntax has been gradually extended in the course of numerous major JDK releases, and now supports capabilities such as generic programming and function literals (called lambda expressions in Java). Since 2017, a new JDK version is released twice a year, with each release bringing incremental improvements to the language.
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To resolve some of the incompatibilities resulting from 's properties, C++11 added two new classes: and (made up of the new types and ), which are the given number of bits per code unit on all platforms. C++11 also added new string literals of 16-bit and 32-bit "characters" and syntax for putting Unicode code points into null- terminated (C-style) strings. A is guaranteed to be specializable for any type with a struct to accompany it. As of C++11, only , , and specializations are required to be implemented in the standard library; any other types are implementation-defined.
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It may be possible to modify the values of (mutable) literals in program code. For instance, if a function returns a quoted form, and the code that calls the function modifies the form, this may alter the behavior of the function on subsequent invocations. (defun should-be-constant () '(one two three)) (let ((stuff (should-be-constant))) (setf (third stuff) 'bizarre)) ; bad! (should-be- constant) ; returns (one two bizarre) Modifying a quoted form like this is generally considered bad style, and is defined by ANSI Common Lisp as erroneous (resulting in "undefined" behavior in compiled files, because the file-compiler can coalesce similar constants, put them in write-protected memory, etc.).
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File formats can use either ordering; some formats use a mixture of both. The term may also be used more generally for the internal ordering of any representation, such as the digits in a numeral system or the sections of a date. Numbers in place-value notation are written with their digits in big-endian order, even in right-to-left scripts. Similarly, programming languages use big-endian digit ordering for numeric literals as well as big-endian way of speaking for bit-shift operations (namely “left” [to be associated with low address] shifts towards the MSB), regardless of the endianness of the target architecture.
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The Pathetic Fallacy traveled with Jack Horner, taking on the role of his sidekick, being somewhat naive and frequently confused, although he had lucid moments when he shows a great deal of knowledge about how stories work. He regards inanimate objects (which are, of course, generally quite animate in his presence) as friends and talks to them frequently. In one of his lucid moments, he refuses to join the Literals in the new universe created for them by the Deus ex Machina and willingly sacrifices his powers. Reasoning that the new universe will develop a Pathetic Fallacy when the need will arise, he returns at Jack's side.
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In computer programming, an anonymous function (function literal, lambda abstraction, or lambda expression) is a function definition that is not bound to an identifier. Anonymous functions are often arguments being passed to higher-order functions, or used for constructing the result of a higher-order function that needs to return a function. If the function is only used once, or a limited number of times, an anonymous function may be syntactically lighter than using a named function. Anonymous functions are ubiquitous in functional programming languages and other languages with first-class functions, where they fulfil the same role for the function type as literals do for other data types.
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Many high-level programming languages, and many assemblers, offer a macro facility where the programmer can define, generally at the beginning of a source file or in a separate definition file, names for different values. A preprocessor then replaces these names with the appropriate values before compiling, resulting in something functionally identical to using literals, with the speed advantages of immediate mode. Because it can be difficult to maintain code where all values are written literally, if a value is used in any repetitive or non- obvious way, it is often done as a macro. A third way is by declaring and defining a variable as being "constant".
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Either the CNF formula Φ is found to comprise a consistent set of literals--that is, there is no `l` and `¬l` for any literal `l` in the formula. If this is the case, the variables can be trivially satisfied by setting them to the respective polarity of the encompassing literal in the valuation. Otherwise, when the formula contains an empty clause, the clause is vacuously false because a disjunction requires at least one member that is true for the overall set to be true. In this case, the existence of such a clause implies that the formula (evaluated as a conjunction of all clauses) cannot evaluate to true and must be unsatisfiable.
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Apache Empire-db is a Java library that provides a high level object-oriented API for accessing relational database management systems (RDBMS) through JDBC. Apache Empire-db is open source and provided under the Apache License 2.0 from the Apache Software Foundation. Compared to Object-relational mapping (ORM) or other data persistence solutions such as Hibernate, iBATIS or TopLink Empire- db does not use XML files or Java annotations to provide a mapping of plain (old) Java object (POJO's) to database tables, views and columns. Instead Empire-db uses a Java object model to describe the underlying data model and an API that works almost solely with object references rather than string literals.
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Generally lexical grammars are context-free, or almost so, and thus require no looking back or ahead, or backtracking, which allows a simple, clean, and efficient implementation. This also allows simple one-way communication from lexer to parser, without needing any information flowing back to the lexer. There are exceptions, however. Simple examples include: semicolon insertion in Go, which requires looking back one token; concatenation of consecutive string literals in Python, which requires holding one token in a buffer before emitting it (to see if the next token is another string literal); and the off-side rule in Python, which requires maintaining a count of indent level (indeed, a stack of each indent level).
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Like many Fables, though, he was taken to Golden Boughs Retirement Village and was stripped of his memories so that he could be made into an ordinary human being. When he begins to regain his memories, he is recaptured so that the process can be repeated. In that process, it is implied he is one of the most powerful Literals in existence, and the soldiers sent to capture him imply that even all of them with their guns could only irritate him, at best, if he fought back. Nonetheless, they manage to bring him back peacefully, where it is revealed Revise is actually his son, and the Pathetic Fallacy is his father.
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After receiving his powers one of the first things he does is to change his name which he decides to call himself Jack. Although briefly distracted by the similarities between Wicked John and Jack Horner, Jack Frost manages to find his father at the Farm. Jack Horner, annoyed by his son's childish insistence, tricks him into believing that he must first complete a great quest before he has the right to ask his father any questions. With this objective in mind, Jack Frost takes part in the battle between Fables and Literals, ultimately turning the tide in favor of the Fables by freezing Kevin Thorn before he can write an end for the current universe.
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Moreover, the search can be carried out sequentially, one node at a time, or in parallel, many nodes simultaneously. SLD resolution is also non-deterministic in the sense, mentioned earlier, that the selection rule is not determined by the inference rule, but is determined by a separate decision procedure, which can be sensitive to the dynamics of the program execution process. The SLD resolution search space is an or-tree, in which different branches represent alternative computations. In the case of propositional logic programs, SLD can be generalised so that the search space is an and-or tree, whose nodes are labelled by single literals, representing subgoals, and nodes are joined either by conjunction or by disjunction.
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Like many programming languages in the Lisp family, Clojure contains an implementation of a linked list, but unlike other dialects its implementation of a Linked List has enforced persistence instead of being persistent by convention. Clojure also has syntax literals for efficient implementations of persistent vectors, maps, and sets based on persistent hash array mapped tries. These data structures implement the mandatory read-only parts of the Java collections framework. The designers of the Clojure language advocate the use of persistent data structures over mutable data structures because they have value semantics which gives the benefit of making them freely shareable between threads with cheap aliases, easy to fabricate, and language independent.
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In computer science, and specifically in compiler and assembler design, a literal pool is a lookup table used to hold literals during assembly and execution. Multiple (local) literal pools are typically used only for computer architectures that lack branch instructions for long jumps, or have a set of instructions optimized for shorter jumps. Examples of such architectures include ARM architecture and the IBM System/360 and later architectures, which had a number of instructions which took 12-bit address offsets. In this case, the compiler would create a literal table on every 4K page; any branches whose target was less than 4K bytes away could be taken immediately; longer branches required an address lookup via the literal table.
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The left-hand side of a rule is called selector and the right-hand side is called the instruction. Such sets of rules are collected in a stylesheet (or several cascading stylesheets) and the application (a GSS engine) responsible for styling RDF model, evaluates relevant rules on data model (resources, literals and properties) while walking it; that is, if the selector of a rule matches a node (or edge) in the data model, its set of styling instructions are applied to that node (or edge). Conflicts between rules matching the same node (or edge) are resolved by giving different priority to rules in the stylesheets and most specific selector if conflicting rules are in the same stylesheet.
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The basic backtracking algorithm runs by choosing a literal, assigning a truth value to it, simplifying the formula and then recursively checking if the simplified formula is satisfiable; if this is the case, the original formula is satisfiable; otherwise, the same recursive check is done assuming the opposite truth value. This is known as the splitting rule, as it splits the problem into two simpler sub-problems. The simplification step essentially removes all clauses that become true under the assignment from the formula, and all literals that become false from the remaining clauses. The DPLL algorithm enhances over the backtracking algorithm by the eager use of the following rules at each step: ; Unit propagation : If a clause is a unit clause, i.e.
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In some programming language environments (at least one proprietary Lisp implementation, for example), the value used as the null pointer (called `nil` in Lisp) may actually be a pointer to a block of internal data useful to the implementation (but not explicitly reachable from user programs), thus allowing the same register to be used as a useful constant and a quick way of accessing implementation internals. This is known as the `nil` vector. In languages with a tagged architecture, a possibly null pointer can be replaced with a tagged union which enforces explicit handling of the exceptional case; in fact, a possibly null pointer can be seen as a tagged pointer with a computed tag. Programming languages use different literals for the null pointer.
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The place was named after Sir James George Frazer's The Golden Bough, a wide-ranging comparative study of mythology and religion. Americana is the American Fable-land from which characters such as Paul Bunyan, Natty Bumppo and Huckleberry Finn came from. These locations are controlled by a number of literals who were written off as physical embodiment of literary ideals and genre. March 25, 2010 Examples of these characters include Mr. Revise who is the embodiment of censorship and revision, his brother Bookburner who is the personification of book burning, their father Gary the Pathetic Fallacy who is the personification of anthropomorphic non-living objects, Dex the Deus Ex Machina, Kevin Thorne who was the embodiment of actual writing and his archenemy Writer's Block.
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Libraries are Hillary's place of power, while the open road is Priscilla's. She claims to know "shortcuts to anywhere," which she uses to reach Kevin Thorn's hideout ahead of Snow White and Bigby. It is implied that all three sisters give up their powers when they decide to stay in the Fables universe instead of accompanying the other literals into the new one provided by "Dex" (Deus Ex Machina, the Literal embodiment of the dramatic concept) - however, Robin seems to be able to communicate with a stone lion at the end of Jack of Fables (unless she was just acting crazy and actually found another way to unlock a secret passage). The sisters decide to travel the world with their nephew, the current Jack Frost.
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In logic programming and datalog, computation and query evaluation are performed by representing the negation of a problem to be solved as a goal clause. For example, the problem of solving the existentially quantified conjunction of positive literals: :∃X (p ∧ q ∧ ... ∧ t) is represented by negating the problem (denying that it has a solution), and representing it in the logically equivalent form of a goal clause: :∀X (false ← p ∧ q ∧ ... ∧ t) In Prolog this is written as: :- p, q, ..., t. Solving the problem amounts to deriving a contradiction, which is represented by the empty clause (or "false"). The solution of the problem is a substitution of terms for the variables in the goal clause, which can be extracted from the proof of contradiction.
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250px Let c_0, ... , c_{2^n-1} be the outputs of a truth table for the function P of n variables, such that the index of the c_i's corresponds to the binary indexing of the mintermsA minterm is the Boolean counterpart of a Zhegalkin monomial. For an n-variable context, there are 2^n Zhegalkin monomials and 2^n Boolean minterms as well. A minterm for an n-variable context consists of an AND-product of n literals, each literal either being a variable in the context or the NOT-negation of such a variable. Moreover, for each variable in the context there must appear exactly once in each minterm a corresponding literal (either the assertion or negation of that variable).
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To go from a Zhegalkin polynomial to a truth-table, it is possible to fill out the top row of the triangular table with the coefficients of the Zhegalkin polynomial (putting in zeroes for any combinations of positive literals not in the polynomial). Then successively compute rows from top to bottom by applying XOR to each pair of horizontally adjacent cells in order to fill the cell immediately to the bottom of the leftmost cell of each pair. When the entire triangular table is filled then the leftmost column of it can be copied to column P of the truth table. As an aside, note that this method of calculation corresponds to the method of operation of the elementary cellular automaton called Rule 102.
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Data types usually did not need to be specified by the programmer; conversion happened transparently in the background between strings and numbers. There were no classes or data structures in the traditional sense; in their place were special string literals, or "lists" of "items" delimited by commas (in later versions the "itemDelimiter" property allowed choosing an arbitrary character). In the late 1980s Apple considered using HyperCard's HyperTalk scripting language as the standard language across the company and within its classic Mac OS operating system, as well as for interprocess communication between Apple and non-Apple products. The company did not oppose the development of imitations like SuperCard, but it created the HyperTalk Standards Committee to avoid incompatibility between language variants.
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For most practical applications, as well as for applications that require non-monotonic reasoning in artificial intelligence, Horn clause logic programs need to be extended to normal logic programs, with negative conditions. A clause in a normal logic program has the form: :`H :- A1, …, An, not B1, …, not Bn. ` and is read declaratively as a logical implication: :`H if A1 and … and An and not B1 and … and not Bn.` where `H` and all the `Ai` and `Bi` are atomic formulas. The negation in the negative literals ` not Bi` is commonly referred to as "negation as failure", because in most implementations, a negative condition ` not Bi` is shown to hold by showing that the positive condition ` Bi` fails to hold. For example: canfly(X) :- bird(X), not abnormal(X).
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However, this typing mechanism eliminates the need for predicates such as isPerson(X) or isLocation(Y), and need not consider livesAt(A,B) when A and B are defined to be person variables, reducing the search space. Additionally, typing can improve the accuracy of the resulting rule by eliminating from consideration impossible literals such as livesAt(A,B) which may nevertheless appear to have a high information gain. Rather than implementing trivial predicates such as equals(X,X) or between(X,X,Y), FOCL introduces implicit constraints on variables, further reducing search space. Some predicates must have all variables unique, others must have commutativity (adjacent(X,Y) is equivalent to adjacent(Y,X)), still others may require that a particular variable be present in the current clause, and many other potential constraints.
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When the Literals leave the main universe to write a new one, Jack Frost stays back with his aunts, the Page Sisters, forswearing his bumbling father and unsure of his future. On Hillary and Priscilla's advice, Jack Frost divests himself of Lumi's powers. However, to his great surprise, instead of returning the meek, sickly kid he was, he turns into a quite handsome young man with the stamina and physical prowess of his father and the innate ability to hop between dimensions. Joining forces with Gepetto's wooden owl, briefly tasked by the Adversary in spying the Homelands, whom he names "McDuff", he starts a career as a hero for hire, with McDuff acting as the brains of the operation, and the good-natured, courageous, but trusty and still naive Jack acting as the brawn.
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A different mechanism for ensuring the correct interaction between formulae referring to different worlds is to switch from formulae to labeled formulae: instead of writing A, one would write w:A to make it explicit that A holds in world w. All propositional expansion rules are adapted to this variant by stating that they all refer to formulae with the same world label. For example, w:A \wedge B generates two nodes labeled with w:A and w:B; a branch is closed only if it contains two opposite literals of the same world, like w:a and w: eg a; no closure is generated if the two world labels are different, like in w:a and w': eg a. The modal expansion rule may have a consequence that refer to a different worlds.
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LZMA encoders can freely decide which match to output, or whether to ignore the presence of matches and output literals anyway. The ability to recall the 4 most recently used distances means that, in principle, using a match with a distance that will be needed again later may be globally optimal even if it is not locally optimal, and as a result of this, optimal LZMA compression probably requires knowledge of the whole input and might require algorithms too slow to be usable in practice. Due to this, practical implementations tend to employ non-global heuristics. The xz encoders use a value called nice_len (the default is 64): when any match of length at least nice_len is found, the encoder stops the search and outputs it, with the maximum matching length.
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A string literal or anonymous string is a type of literal in programming for the representation of a string value within the source code of a computer program. Most often in modern languages this is a quoted sequence of characters (formally "bracketed delimiters"), as in `x = "foo"`, where `"foo"` is a string literal with value `foo` – the quotes are not part of the value, and one must use a method such as escape sequences to avoid the problem of delimiter collision and allow the delimiters themselves to be embedded in a string. However, there are numerous alternate notations for specifying string literals, particularly more complicated cases, and the exact notation depends on the individual programming language in question. Nevertheless, there are some general guidelines that most modern programming languages follow.
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In formal logic, a knowledge base KB is complete if there is no formula α such that KB ⊭ α and KB ⊭ ¬α. Example of knowledge base with incomplete knowledge: KB := { A ∨ B } Then we have KB ⊭ A and KB ⊭ ¬A. In some cases, a consistent knowledge base can be made complete with the closed world assumption—that is, adding all not-entailed literals as negations to the knowledge base. In the above example though, this would not work because it would make the knowledge base inconsistent: KB' = { A ∨ B, ¬A, ¬B } In the case where KB := { P(a), Q(a), Q(b) }, KB ⊭ P(b) and KB ⊭ ¬P(b), so, with the closed world assumption, KB' = { P(a), ¬P(b), Q(a), Q(b) }, where KB' ⊨ ¬P(b).
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The clauses in P define a set of non-abducible predicates and through this they provide a description (or model) of the problem domain. The integrity constraints in IC specify general properties of the problem domain that need to be respected in any solution of a problem. A problem, G, which expresses either an observation that needs to be explained or a goal that is desired, is represented by a conjunction of positive and negative (NAF) literals. Such problems are solved by computing "abductive explanations" of G. An abductive explanation of a problem G is a set of positive (and sometimes also negative) ground instances of the abducible predicates, such that, when these are added to the logic program P, the problem G and the integrity constraints IC both hold.
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Other high-level languages such as Python, JavaScript and Tcl have other facilities for multiline strings. Here documents can be treated either as files or strings. Some shells treat them as a format string literal, allowing variable substitution and command substitution inside the literal. The most common syntax for here documents, originating in Unix shells, is `<<` followed by a delimiting identifier (often the word EOF or END), followed, starting on the next line, by the text to be quoted, and then closed by the same delimiting identifier on its own line. This syntax is because here documents are formally stream literals, and the content of the document is redirected to stdin (standard input) of the preceding command; the here document syntax is by analogy with the syntax for input redirection, which is `<` “take input from the following file”.
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Each synset encodes the relation of equivalence between a number of lexical items - LITERALS (at least one should be explicitly represented in the SYNSET), each of them having a unique meaning (specified by the value of SENSE) - which pertain to one and the same part of speech (specified as the value of POS) and represent one and the same lexical meaning (specified as the value of DEF). Each synset is linked to its counterpart in PWN 3.0 by means of a unique identification number - ID. The common synsets in the Balkan languages are marked as common concepts subsets - BCS. In a monolingual database, a synset should be linked to at least one other synset through an intralingual relation. Non-obligatory information may also be encoded such as examples of usage, stylistic peculiarities, morphological or syntactic properties, author and last edit details.
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Software distributors use executable compression for a variety of reasons, primarily to reduce the secondary storage requirements of their software; as executable compressors are specifically designed to compress executable code, they often achieve better compression ratio than standard data compression facilities such as gzip, zip or bzip2 . This allows software distributors to stay within the constraints of their chosen distribution media (such as CD-ROM, DVD-ROM, or Floppy disk), or to reduce the time and bandwidth customers require to access software distributed via the Internet. Executable compression is also frequently used to deter reverse engineering or to obfuscate the contents of the executable (for example, to hide the presence of malware from antivirus scanners) by proprietary methods of compression and/or added encryption. Executable compression can be used to prevent direct disassembly, mask string literals and modify signatures.
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Formally, a one-in-three 3-SAT problem is given as a generalized conjunctive normal form with all generalized clauses using a ternary operator R that is TRUE just if exactly one of its arguments is. When all literals of a one-in-three 3-SAT formula are positive, the satisfiability problem is called one-in-three positive 3-SAT. One-in-three 3-SAT, together with its positive case, is listed as NP-complete problem "LO4" in the standard reference, Computers and Intractability: A Guide to the Theory of NP-Completeness by Michael R. Garey and David S. Johnson. One-in-three 3-SAT was proved to be NP-complete by Thomas Jerome Schaefer as a special case of Schaefer's dichotomy theorem, which asserts that any problem generalizing Boolean satisfiability in a certain way is either in the class P or is NP-complete.
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A panel in Jack of Fables # 33 showing the characters in the series, including both the Fables and the Literals Unlike Fables which was written as a mature comic with serious human drama and a gritty tone, Jack of Fables was written as a comedy story with slapstick, violence and fourth wall breaking. Josh Flanagan of IFanboy remarked that it pokes fun on the serious premise of Fables by being a "bit sillier" and having a less-serious tone than the main series. Lilah Sturges actually wrote the story with focus on putting the character Jack Horner into an ever-increasing number of mishaps and troubles as the series went on. To top it all of, Willingham and Sturges decided to kill off all of the characters in the series by the last story arc, as a sort of a final humor that was known in Jack of Fables.
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From the perspective of knowledge representation, a set of ground atoms can be thought of as a description of a complete state of knowledge: the atoms that belong to the set are known to be true, and the atoms that do not belong to the set are known to be false. A possibly incomplete state of knowledge can be described using a consistent but possibly incomplete set of literals; if an atom p does not belong to the set and its negation does not belong to the set either then it is not known whether p is true or false. In the context of logic programming, this idea leads to the need to distinguish between two kinds of negation — negation as failure, discussed above, and strong negation, which is denoted here by \sim.Gelfond and Lifschitz [1991] call the second negation classical and denote it by eg.
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Satisfiability of the formula is detected either when all variables are assigned without generating the empty clause, or, in modern implementations, if all clauses are satisfied. Unsatisfiability of the complete formula can only be detected after exhaustive search. The DPLL algorithm can be summarized in the following pseudocode, where Φ is the CNF formula: Input: A set of clauses Φ. Output: A Truth Value. function DPLL(Φ) if Φ is a consistent set of literals then return true; if Φ contains an empty clause then return false; for every unit clause {l} in Φ do Φ ← unit-propagate(l, Φ); for every literal l that occurs pure in Φ do Φ ← pure-literal-assign(l, Φ); l ← choose- literal(Φ); return DPLL(Φ ∧ {l}) or DPLL(Φ ∧ {not(l)}); In this pseudocode, `unit-propagate(l, Φ)` and `pure-literal-assign(l, Φ)` are functions that return the result of applying unit propagation and the pure literal rule, respectively, to the literal `l` and the formula `Φ`.
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Brotli is a data format specification for data streams compressed with a specific combination of the general-purpose LZ77 lossless compression algorithm, Huffman coding and 2nd order context modelling. Brotli is a compression algorithm developed by Google and works best for text compression. Google employees Jyrki Alakuijala and Zoltán Szabadka initially developed Brotli to decrease the size of transmissions of WOFF2 web fonts, and in that context Brotli was a continuation of the development of zopfli, which is a zlib-compatible implementation of the standard gzip and deflate specifications. Brotli allows a denser packing than gzip and deflate because of several algorithmic and format level improvements: the use of context models for literals and copy distances, describing copy distances through past distances, use of move-to-front queue in entropy code selection, joint-entropy coding of literal and copy lengths, the use of graph algorithms in block splitting, and a larger backward reference window are example improvements.
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Connection is a condition over tableau that forbids expanding a branch using clauses that are unrelated to the literals that are already in the branch. Connection can be defined in two ways: ; strong connectedness : when expanding a branch, use an input clause only if it contains a literal that can be unified with the negation of the literal in the current leaf ; weak connectedness : allow the use of clauses that contain a literal that unifies with the negation of a literal on the branch Both conditions apply only to branches consisting not only of the root. The second definition allows for the use of a clause containing a literal that unifies with the negation of a literal in the branch, while the first only further constraint that literal to be in leaf of the current branch. If clause expansion is restricted by connectedness (either strong or weak), its application produces a tableau in which substitution can applied to one of the new leaves, closing its branch.
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Used in this way, goal clauses are similar to conjunctive queries in relational databases, and Horn clause logic is equivalent in computational power to a universal Turing machine. The Prolog notation is actually ambiguous, and the term “goal clause” is sometimes also used ambiguously. The variables in a goal clause can be read as universally or existentially quantified, and deriving “false” can be interpreted either as deriving a contradiction or as deriving a successful solution of the problem to be solved. Van Emden and Kowalski (1976) investigated the model theoretic properties of Horn clauses in the context of logic programming, showing that every set of definite clauses D has a unique minimal model M. An atomic formula A is logically implied by D if and only if A is true in M. It follows that a problem P represented by an existentially quantified conjunction of positive literals is logically implied by D if and only if P is true in M. The minimal model semantics of Horn clauses is the basis for the stable model semantics of logic programs.
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Matches of size less than N are instead found by simply looking at the corresponding hash table, which either contains the latest such match, if any, or a string that hashes to the same value; in the latter case, the encoder won't be able to find the match. This issue is mitigated by the fact that for distant short matches using multiple literals might require less bits, and having hash conflicts in nearby strings is relatively unlikely; using larger hash tables or even direct lookup tables can reduce the problem at the cost of higher cache miss rate and thus lower performance. Note that all matches need to be validated to check that the actual bytes match currently at that specific dictionary position match, since the hashing mechanism only guarantees that at some past time there were characters hashing to the hash table bucket index (some implementations may not even guarantee that, because they don't initialize the data structures). LZMA uses Markov chains, as implied by "M" in its name.
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If existential quantification over vertices were also allowed, the resulting complexity class would be equal to NP (more precisely, the class of those properties of relational structures that are in NP), a fact known as Fagin's theorem. For example, SNP contains 3-Coloring (the problem of determining whether a given graph is 3-colorable), because it can be expressed by the following formula: : \exists S_1 \exists S_2 \exists S_3 \, \forall u \forall v \, \bigl( S_1(u) \vee S_2(u) \vee S_3(u) \bigr) \, \wedge \, \bigl( E(u,v)\,\implies\,( eg S_1(u) \vee eg S_1(v))\,\wedge\,\left( eg S_2(u) \vee eg S_2(v)\right)\,\wedge\,( eg S_3(u) \vee eg S_3(v)) \bigr) . Here E denotes the adjacency relation of the input graph, while the sets (unary relations) S_1,S_2,S_3 correspond to sets of vertices colored with one of the 3 colors. Similarly, SNP contains the k-SAT problem: the boolean satisfiability problem (SAT) where the formula is restricted to conjunctive normal form and to at most k literals per clause, where k is fixed.
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Every tableau can be considered as a graphical representation of a formula, which is equivalent to the set the tableau is built from. This formula is as follows: each branch of the tableau represents the conjunction of its formulae; the tableau represents the disjunction of its branches. The expansion rules transforms a tableau into one having an equivalent represented formula. Since the tableau is initialized as a single branch containing the formulae of the input set, all subsequent tableaux obtained from it represent formulae which are equivalent to that set (in the variant where the initial tableau is the single node labeled true, the formulae represented by tableaux are consequences of the original set.) A tableau for the satisfiable set {a⋀c,¬a⋁b}: all rules have been applied to every formula on every branch, but the tableau is not closed (only the left branch is closed), as expected for satisfiable sets The method of tableaux works by starting with the initial set of formulae and then adding to the tableau simpler and simpler formulae until contradiction is shown in the simple form of opposite literals.
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Lexical analysis, 2.4.2. String literal concatenation: "Multiple adjacent string literals (delimited by whitespace), possibly using different quoting conventions, are allowed, and their meaning is the same as their concatenation." which copied it from C.Python-ideas, "Implicit string literal concatenation considered harmful?", Guido van Rossum, May 10, 2013 Notably, this concatenation happens at compile time, during lexical analysis (as a phase following initial tokenization), and is contrasted with both run time string concatenation (generally with the `+` operator)The Python Language Reference, 2. Lexical analysis, 2.4.2. String literal concatenation: "Note that this feature is defined at the syntactical level, but implemented at compile time. The ‘+’ operator must be used to concatenate string expressions at run time." and concatenation during constant folding, which occurs at compile time, but in a later phase (after phrase analysis or "parsing"). Most languages, such as C#, Java and Perl, do not support implicit string literal concatenation, and instead require explicit concatenation, such as with the `+` operator (this is also possible in D and Python, but illegal in C/C++ – see below); in this case concatenation may happen at compile time, via constant folding, or may be deferred to run time.
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