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Metasyntax
In logic and computer science, a metasyntax describes the allowable structure and composition of phrases and sentences of a metalanguage, which is used to describe either a natural language or a computer programming language.Sellink, Alex, and Chris Verhoef.Development, assessment, and reengineering of language descriptions" Software Maintenance and Reengineering, 2000. Proceedings of the Fourth European. IEEE, 2000. Some of the widely used formal metalanguages for computer languages are Backus–Naur form (BNF), extended Backus–Naur form (EBNF), Wirth syntax notation (WSN), and augmented Backus–Naur form (ABNF). These metalanguages have their own metasyntax each composed of terminal symbols, nonterminal symbols, and ''metasymbols''. A terminal symbol, such as a word or a token, is a stand-alone structure in a language being defined. A nonterminal symbol represents a syntactic category, which defines one or more valid phrasal or sentence structure consisted of an n-element subs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metasemantics
In the philosophy of language and metaphysics, metasemantics is the study of the foundations of natural language semantics (the philosophical study of meaning). Metasemantics searches for "the proper understanding of compositionality, the object of truth-conditional analysis, metaphysics of reference, as well as, and most importantly, the scope of semantic theory itself" and asks "how it is that expressions become endowed with their semantic significance".Ori Simchen, ''Semantics, Metasemantics, Aboutness'', Oxford University Press, 2017, p. xiii. See also * Metasyntax * Metapragmatics In linguistics, metapragmatics is the study of how the effects and conditions of language use themselves become objects of discourse. The term is commonly associated with the semiotically-informed linguistic anthropology of Michael Silverstein. Ov ... References Semantics Meaning (philosophy of language) {{philosophy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metapragmatics
In linguistics, metapragmatics is the study of how the effects and conditions of language use themselves become objects of discourse. The term is commonly associated with the semiotically-informed linguistic anthropology of Michael Silverstein. Overview Metapragmatic signalling allows participants to construe what is going on in an interaction. Examples include: * Describing the "correct way" of using language ("I before E except after C."), * Specifying under which conditions a specific kind of communication are, or should be, used ("You should never tell a dirty joke at a funeral."), * Signalling, explicitly or implicitly, the type of social event occurring (explicit: "I promise to be there at 3:00 p.m." implicit: "I will be there at 3:00 p.m.") * Linking speech to another event outside the moment of speaking ("Every day she goes jogging." ). Discussions of linguistic pragmatics—that is, discussions of what speech ''does'' in a particular context—are meta-pragmatic, because t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backus–Naur Form
In computer science, Backus–Naur form () or Backus normal form (BNF) is a metasyntax notation for context-free grammars, often used to describe the syntax of languages used in computing, such as computer programming languages, document formats, instruction sets and communication protocols. It is applied wherever exact descriptions of languages are needed: for instance, in official language specifications, in manuals, and in textbooks on programming language theory. Many extensions and variants of the original Backus–Naur notation are used; some are exactly defined, including extended Backus–Naur form (EBNF) and augmented Backus–Naur form (ABNF). Overview A BNF specification is a set of derivation rules, written as ::= __expression__ where: * is a ''nonterminal'' (variable) and the __expression__ consists of one or more sequences of either terminal or nonterminal symbols; * means that the symbol on the left must be replaced with the expression on the right. * mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wirth Syntax Notation
Wirth syntax notation (WSN) is a metasyntax, that is, a formal way to describe formal languages. Originally proposed by Niklaus Wirth in 1977 as an alternative to Backus–Naur form (BNF). It has several advantages over BNF in that it contains an explicit iteration construct, and it avoids the use of an explicit symbol for the empty string (such as or ε). WSN has been used in several International Organization for Standardization, international standards, starting with ISO 10303-21. It was also used to define the syntax of ISO 10303-11, EXPRESS, the data modelling language of ISO 10303, STEP. WSN defined in itself SYNTAX = . PRODUCTION = IDENTIFIER "=" EXPRESSION "." . EXPRESSION = TERM . TERM = FACTOR . FACTOR = IDENTIFIER , LITERAL , "[" EXPRESSION "]" , "(" EXPRESSION ")" , "" . IDENTIFIER = letter . LITERAL = """" character """" . The equals sign indicates a production. The element on the left ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syntactic
In linguistics, syntax () is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure (constituency), agreement, the nature of crosslinguistic variation, and the relationship between form and meaning (semantics). There are numerous approaches to syntax that differ in their central assumptions and goals. Etymology The word ''syntax'' comes from Ancient Greek roots: "coordination", which consists of ''syn'', "together", and ''táxis'', "ordering". Topics The field of syntax contains a number of various topics that a syntactic theory is often designed to handle. The relation between the topics is treated differently in different theories, and some of them may not be considered to be distinct but instead to be derived from one another (i.e. word order can be seen as the result of movement rules derived from grammatical relations). Seq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logic
Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premises in a topic-neutral way. When used as a countable noun, the term "a logic" refers to a logical formal system that articulates a proof system. Formal logic contrasts with informal logic, which is associated with informal fallacies, critical thinking, and argumentation theory. While there is no general agreement on how formal and informal logic are to be distinguished, one prominent approach associates their difference with whether the studied arguments are expressed in formal or informal languages. Logic plays a central role in multiple fields, such as philosophy, mathematics, computer science, and linguistics. Logic studies arguments, which consist of a set of premises together with a conclusion. Premises and conclusions are usually un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ada (programming Language)
Ada is a structured, statically typed, imperative, and object-oriented high-level programming language, extended from Pascal and other languages. It has built-in language support for '' design by contract'' (DbC), extremely strong typing, explicit concurrency, tasks, synchronous message passing, protected objects, and non-determinism. Ada improves code safety and maintainability by using the compiler to find errors in favor of runtime errors. Ada is an international technical standard, jointly defined by the International Organization for Standardization (ISO), and the International Electrotechnical Commission (IEC). , the standard, called Ada 2012 informally, is ISO/IEC 8652:2012. Ada was originally designed by a team led by French computer scientist Jean Ichbiah of CII Honeywell Bull under contract to the United States Department of Defense (DoD) from 1977 to 1983 to supersede over 450 programming languages used by the DoD at that time. Ada was named after Ada Lovelace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comparison Of Parser Generators
This is a list of notable lexer generators and parser generators for various language classes. Regular languages Regular languages are a category of languages (sometimes termed Chomsky Type 3) which can be matched by a state machine (more specifically, by a deterministic finite automaton or a nondeterministic finite automaton) constructed from a regular expression. In particular, a regular language can match constructs like "A follows B", "Either A or B", "A, followed by zero or more instances of B", but cannot match constructs which require consistency between non-adjacent elements, such as "some instances of A followed by the same number of instances of B", and also cannot express the concept of recursive "nesting" ("every A is eventually followed by a matching B"). A classic example of a problem which a regular grammar cannot handle is the question of whether a given string contains correctly-nested parentheses. (This is typically handled by a Chomsky Type 2 grammar, also te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptive Grammar
An adaptive grammar is a formal grammar that explicitly provides mechanisms within the formalism to allow its own production rules to be manipulated. Overview John N. Shutt defines adaptive grammar as a grammatical formalism that allows rule sets (aka sets of production rules) to be explicitly manipulated within a grammar. Types of manipulation include rule addition, deletion, and modification. Early history The first description of grammar adaptivity (though not under that name) in the literature is generallyChristiansen, Henning, "Survey of Adaptable Grammars" ''ACM SIGPLAN Notices'', Vol. 25 No. 11, pp. 35-44, Nov. 1990.Shutt, John N., Recursive Adaptable Grammars', Master’s Thesis, Worcester Polytechnic Institute, 1993. (16 December 2003 emended revision.)Jackson, Quinn Tyler, Adapting to Babel: Adaptivity and Context-Sensitivity in Parsing', Ibis Publications, Plymouth, Massachusetts, March 2006. taken to be in a paper by Alfonso Caracciolo di Forino published in 1963.Cara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J (programming Language)
The J programming language, developed in the early 1990s by Kenneth E. Iverson and Roger Hui, is an array programming language based primarily on APL (also by Iverson). To avoid repeating the APL special-character problem, J uses only the basic ASCII character set, resorting to the use of the dot and colon as ''inflections'' to form short words similar to '' digraphs''. Most such ''primary'' (or ''primitive'') J words serve as mathematical symbols, with the dot or colon extending the meaning of the basic characters available. Also, many characters which in other languages often must be paired (such as [] "" `` or ) are treated by J as stand-alone words or, when inflected, as single-character roots of multi-character words. J is a very terse array programming language, and is most suited to mathematical and statistical programming, especially when performing operations on matrices. It has also been used in extreme programming and network performance analysis. Like John Backu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sans-serif
In typography and lettering, a sans-serif, sans serif, gothic, or simply sans letterform is one that does not have extending features called "serifs" at the end of strokes. Sans-serif typefaces tend to have less stroke width variation than serif typefaces. They are often used to convey simplicity and modernity or minimalism. Sans-serif typefaces have become the most prevalent for display of text on computer screens. On lower-resolution digital displays, fine details like serifs may disappear or appear too large. The term comes from the French word , meaning "without" and "serif" of uncertain origin, possibly from the Dutch word meaning "line" or pen-stroke. In printed media, they are more commonly used for display use and less for body text. Before the term "sans-serif" became common in English typography, a number of other terms had been used. One of these outmoded terms for sans-serif was gothic, which is still used in East Asian typography and sometimes seen in typeface na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Italic Font
In typography, italic type is a cursive font based on a stylised form of calligraphic handwriting. Owing to the influence from calligraphy, italics normally slant slightly to the right. Italics are a way to emphasise key points in a printed text, to identify many types of creative works, to cite foreign words or phrases, or, when quoting a speaker, a way to show which words they stressed. One manual of English usage described italics as "the print equivalent of underlining"; in other words, underscore in a manuscript directs a typesetter to use italic. The name comes from the fact that calligraphy-inspired typefaces were first designed in Italy, to replace documents traditionally written in a handwriting style called chancery hand. Aldus Manutius and Ludovico Arrighi (both between the 15th and 16th centuries) were the main type designers involved in this process at the time. Along with blackletter and Roman type, it served as one of the major typefaces in the history of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
