command generates OCaml lexers from a set of regular
expressions with associated semantic actions, in the style of
on the input file
lexer.mll produces OCaml code for a lexical analyzer in file
This file defines one lexing function per entry point in the lexer
definition. These functions have the same names as the entry
points. Lexing functions take as argument a lexer buffer, and return
the semantic attribute of the corresponding entry point.
Lexer buffers are an abstract data type implemented in the standard
library module Lexing. The functions Lexing.from_channel,
Lexing.from_string and Lexing.from_function create
lexer buffers that read from an input channel, a character string, or
any reading function, respectively.
When used in conjunction with a parser generated by
the semantic actions compute a value belonging to the type token defined
by the generated parsing module.