CamlinternalMenhirLib.LexerUtil(3)

NAME
CamlinternalMenhirLib.LexerUtil - no description

Module
Module CamlinternalMenhirLib.LexerUtil

Documentation

Module LexerUtil
 : sig end

val init : string -> Lexing.lexbuf -> Lexing.lexbuf

init filename lexbuf initializes the lexing buffer lexbuf so that the positions that are subsequently read from it refer to the file filename . It returns lexbuf .

val read : string -> string * Lexing.lexbuf

read filename reads the entire contents of the file filename and returns a pair of this content (a string) and a lexing buffer that has been initialized, based on this string.

val newline : Lexing.lexbuf -> unit

newline lexbuf increments the line counter stored within lexbuf . It should be invoked by the lexer itself every time a newline character is consumed. This allows maintaining a current the line number in lexbuf .

val range : Lexing.position * Lexing.position -> string

range (startpos, endpos) prints a textual description of the range delimited by the start and end positions startpos and endpos . This description is one line long and ends in a newline character. This description mentions the file name, the line number, and a range of characters on this line. The line number is correct only if newline has been correctly used, as described dabove.

val tabulate : ('a -> bool) -> (unit -> 'a) -> unit -> 'a

tabulate is_eof lexer tabulates the lexer lexer : that is, it immediately runs this lexer all the way until an EOF token is found, stores the tokens in an array in memory, and returns a new lexer which (when invoked) reads tokens from this array. The function lexer is not allowed to raise an exception, and must produce a finite stream of tokens: that is, after a finite number of invocations, it must return a token that is identified by the function is_eof as an EOF token.

Both the existing lexer lexer and the new lexer returned by tabulate
is_eof lexer are functions of type unit -> 'a , where the type 'a is likely to be instantiated with a triple of a token and two positions, as per the revised lexer API described in the module CamlinternalMenhirLib.Convert .