In computer science, a lexical grammar is the syntax of tokens. That is, the rules governing how a character sequence is divided up into subsequences of characters, each part of which represents an individual token.
For instance, the lexical grammar for many programming languages specifies that a string starts with a " character and continues until a matching " is found, that an identifier is a sequence of letters and digits, and that a number is a sequence of digits. So in the following character sequence "abc" xyz1 23 the tokens are string, identifier and number (because the space character terminates the sequence of characters forming the identifier.)
Famous quotes containing the word grammar:
“Syntax is the study of the principles and processes by which sentences are constructed in particular languages. Syntactic investigation of a given language has as its goal the construction of a grammar that can be viewed as a device of some sort for producing the sentences of the language under analysis.”
—Noam Chomsky (b. 1928)