| Noun | 1. | grammar - studies of the formation of basic linguistic units |
| grammar - A formal definition of the syntactic structure of a language
(see syntax), normally given in terms of production rules
which specify the order of constituents and their
sub-constituents in a sentence (a well-formed string in the
language). Each rule has a left-hand side symbol naming a
syntactic category (e.g. "noun-phrase" for a natural language grammar) and a right-hand side which is a sequence
of zero or more symbols. Each symbol may be either a
terminal symbol or a non-terminal symbol. A terminal symbol
corresponds to one "lexeme" - a part of the sentence with
no internal syntactic structure (e.g. an identifier or an
operator in a computer language). A non-terminal symbol is
the left-hand side of some rule. One rule is normally designated as the top-level rule which gives the structure for a whole sentence. A grammar can be used either to parse a sentence (see parser) or to generate one. Parsing assigns a terminal syntactic category to each input token and a non-terminal category to each appropriate group of tokens, up to the level of the whole sentence. Parsing is usually preceded by lexical analysis. Generation starts from the top-level rule and chooses one alternative production wherever there is a choice. See also BNF, yacc, attribute grammar, grammar analysis. |