ocaml/test/Lex/scanner.mll

132 lines
3.6 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* Automatique. Distributed only by permission. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* The lexical analyzer for lexer definitions. *)
{
open Syntax
open Grammar
open Scan_aux
}
rule main = parse
[' ' '\010' '\013' '\009' ] +
{ main lexbuf }
| "(*"
{ comment_depth := 1;
comment lexbuf;
main lexbuf }
| (['A'-'Z' 'a'-'z'] | '_' ['A'-'Z' 'a'-'z' '\'' '0'-'9'])
( '_' ? ['A'-'Z' 'a'-'z' ''' '0'-'9'] ) *
{ match Lexing.lexeme lexbuf with
"rule" -> Trule
| "parse" -> Tparse
| "and" -> Tand
| "eof" -> Teof
| s -> Tident s }
| '"'
{ reset_string_buffer();
string lexbuf;
Tstring(get_stored_string()) }
| "'"
{ Tchar(char lexbuf) }
| '{'
{ let n1 = Lexing.lexeme_end lexbuf in
brace_depth := 1;
let n2 = action lexbuf in
Taction(Location(n1, n2)) }
| '=' { Tequal }
| ";;" { Tend }
| '|' { Tor }
| '_' { Tunderscore }
| "eof" { Teof }
| '[' { Tlbracket }
| ']' { Trbracket }
| '*' { Tstar }
| '?' { Tmaybe }
| '+' { Tplus }
| '(' { Tlparen }
| ')' { Trparen }
| '^' { Tcaret }
| '-' { Tdash }
| eof
{ raise(Lexical_error "unterminated lexer definition") }
| _
{ raise(Lexical_error("illegal character " ^ Lexing.lexeme lexbuf)) }
and action = parse
'{'
{ incr brace_depth;
action lexbuf }
| '}'
{ decr brace_depth;
if !brace_depth = 0 then Lexing.lexeme_start lexbuf else action lexbuf }
| '"'
{ reset_string_buffer();
string lexbuf;
reset_string_buffer();
action lexbuf }
| '\''
{ char lexbuf; action lexbuf }
| "(*"
{ comment_depth := 1;
comment lexbuf;
action lexbuf }
| eof
{ raise (Lexical_error "unterminated action") }
| _
{ action lexbuf }
and string = parse
'"'
{ () }
| '\\' [' ' '\010' '\013' '\009' '\026' '\012'] +
{ string lexbuf }
| '\\' ['\\' '"' 'n' 't' 'b' 'r']
{ store_string_char(char_for_backslash(Lexing.lexeme_char lexbuf 1));
string lexbuf }
| '\\' ['0'-'9'] ['0'-'9'] ['0'-'9']
{ store_string_char(char_for_decimal_code lexbuf 1);
string lexbuf }
| eof
{ raise(Lexical_error "unterminated string") }
| _
{ store_string_char(Lexing.lexeme_char lexbuf 0);
string lexbuf }
and char = parse
[^ '\\'] "'"
{ Lexing.lexeme_char lexbuf 0 }
| '\\' ['\\' '\'' 'n' 't' 'b' 'r'] "'"
{ char_for_backslash (Lexing.lexeme_char lexbuf 1) }
| '\\' ['0'-'9'] ['0'-'9'] ['0'-'9'] "'"
{ char_for_decimal_code lexbuf 1 }
| _
{ raise(Lexical_error "bad character constant") }
and comment = parse
"(*"
{ incr comment_depth; comment lexbuf }
| "*)"
{ decr comment_depth;
if !comment_depth = 0 then () else comment lexbuf }
| '"'
{ reset_string_buffer();
string lexbuf;
reset_string_buffer();
comment lexbuf }
| eof
{ raise(Lexical_error "unterminated comment") }
| _
{ comment lexbuf }