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:
“Grammar is a tricky, inconsistent thing. Being the backbone of speech and writing, it should, we think, be eminently logical, make perfect sense, like the human skeleton. But, of course, the skeleton is arbitrary, too. Why twelve pairs of ribs rather than eleven or thirteen? Why thirty-two teeth? It has something to do with evolution and functionalism—but only sometimes, not always. So there are aspects of grammar that make good, logical sense, and others that do not.”
—John Simon (b. 1925)