What does AG mean in LINGUISTICS

Attribute Grammar is a type of formal grammar used for describing programming languages that define the syntactic structure of the language as well as its semantics. It is typically used to specify a particular language's syntax and static semantics, meaning what can be said in that language and how it should be interpreted. Attribute Grammars also provide tools for generating compilers and interpreters.

An Attribute Grammar defines the syntax of a language using production rules which describe ways to construct phrases from symbols. It also defines attributes associated with each symbol in a phrase and their interactions with one another. When a phrase is analyzed, the attributes associated with each symbol are evaluated according to the production rules defined by the grammar and any transformations are applied accordingly.

One advantage of using an Attribute Grammar is that it allows us to more easily define complex language features such as exception-handling, recursion, or multiple-inheritance. By defining all aspects—syntax and static behavior—of a language in one place, we can gain better control over parsing and semantic analysis activities. Additionally, since all rules are defined explicitly in an attribute grammar, there are fewer hidden side effects when extending or modifying existing code.

Many popular programming languages like Java, C#, Python, Lisp, Ruby, Go etc., have implemented attribute grammars in form of annotations or data-structures embedded as part of their code base. Compilers for these languages rely on attribute grammars extensively during their parsing stage when tokens are identified and grouped into meaningful expressions.

An Attribute Grammar typically contains four components namely - Nonterminal symbols (or variables), Terminal symbols (or lexemes), Production rules (or Rewrite Rules), Attributes associated with each symbol in a phrase (or Semantic Actions). These components behave differently depending on the context they appear in within a sentence structure. Nonterminal symbols represent syntactic categories like nouns or verbs while terminal symbols represent words themselves; production rules can be thought of as templates which indicate how nonterminals interact; finally attributes capture information about values associated with each symbol or lexeme which helps determine if something is valid or not within given context.

Parsing through an attribute grammar requires two steps - Syntax Analysis and Semantic Analysis. During Syntax Analysis, strings (or sentences) written in some language are broken down into individual tokens based upon predefined set of production rules after which structural relationships between them becomes evident depending on context; whereas during Semantic Analysis phase all tokens processed earlier will now be checked against their respective attributes to ensure they obey every condition specified by corresponding rule before being considered valid expression within given programmatic context.

Yes - MAWL(Multiparadigm Automata based Widget Language) is one such programming language created by Microsoft Research whose entire syntax & semantics have been structured around use-case scenarios enabled by underlying attribute grammar framework.

There have been numerous research opportunities revolving around attribute grammars such as designing efficient parsers & compilers for new application domains (like AI); improving error correction/predictive abilities within existing platforms; adding additional restrictions & constraints beyond provided specifications thereby creating more secure environment etc.