lexer.mll

{
open Parser        (* The type token is defined in parser.mli *)
open Lexing
exception Eof
}
rule token = parse
    [' ' '\t' '\n']     { token lexbuf }     (* skip blanks *)
  | '+'            { PLUS }
  | '-'            { MINUS }
  | '<'            { LTHAN }
  | '>'            { GTHAN }
  | "=="           { EQUALITY }
  | '('            { LPAREN }
  | ')'            { RPAREN }
  | '{'            { LBRACE }
  | '}'            { RBRACE }
  | ';'            { SEMICOLON }
  | '='            { EQUALS }
  | "let"          { LET }
  | ':'            { COLON }
  | "i32"          { I32_TYPE }
  | "u32"          { U32_TYPE }
  | "bool"         { BOOL_TYPE }
  | "while"        { WHILE }
  | "if"           { IF }
  | "else"         { ELSE }
  | "true"         { TRUE }
  | "false"        { FALSE }

  | ['0'-'9']+ as lxm { INT(int_of_string lxm) }
  | ['a'-'z' 'A'-'Z']+ as lxm { IDENT(lxm) }

  | eof            { raise Eof }
  | _ { Errors.complain ("ERROR L000: Illegal character " ^ (Char.escaped(Lexing.lexeme_char lexbuf 0))) }