Lexical Grammar
The specification of a programming language often includes a set of rules which defines the lexer. These rules usually consist of regular expressions, and they define the set of possible character sequences that are used to form individual tokens or lexemes.
In programming languages that delimit blocks with tokens (e.g., "{" and "}"), as opposed to off-side rule languages that delimit blocks with indentation, white space is also defined by a regular expression and influences the recognition of other tokens but does not itself contribute tokens. White space is said to be non-significant in such languages.
Read more about this topic: Lexical Analysis
Famous quotes containing the word grammar:
“All the facts of nature are nouns of the intellect, and make the grammar of the eternal language. Every word has a double, treble or centuple use and meaning.”
—Ralph Waldo Emerson (1803–1882)