/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright (C) 2000 Gerwin Klein <lsf@jflex.de>                          *
 * All rights reserved.                                                    *
 *                                                                         *
 * Thanks to Larry Bell and Bob Jamison for suggestions and comments.      *
 *                                                                         *
 * License: BSD                                                            *
 *                                                                         *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

%%

%byaccj

%{
  private Parser yyparser;

  public Yylex(java.io.Reader r, Parser yyparser) {
    this(r);
    this.yyparser = yyparser;
  }
%}

nums = [0-9]+ ("." [0-9]+)?
nls  = \n | \r | \r\n

%%

/* operators */
"+"  { return Parser.PLUS; }
"-"  { return Parser.MINUS; }
"*"  { return Parser.TIMES; }
"/"  { return Parser.DIV; }

/* parenthesis */
"("  { return Parser.LPAR; }
")"  { return Parser.RPAR; }

/* newline */
{nls}   { return Parser.NL; }

/* float */
{nums}  { yyparser.yylval = new ParserVal(Double.parseDouble(yytext()));
         return Parser.NUM; }

/* whitespace */
[ \t]+ { }

\b     { System.err.println("Sorry, backspace doesn't work"); }

/* error fallback */
[^]    { System.err.println("Error: unexpected character '"+yytext()+"'"); return -1; }