bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/parser/grammar/input/GrammarLexer.flex

   1 package org.simantics.parser.grammar.input2;
   2
   3 import org.simantics.parser.grammar.input2.Token;
   4
   5 %%
   6
   7 %public
   8 %char
   9 %unicode
  10 %class GrammarLexer
  11 %function nextToken
  12 %type Token
  13 %yylexthrow RuntimeException
  14 %scanerror RuntimeException
  15 %eofval{
  16     return sym(GrammarTerminals.EOF);
  17 %eofval}
  18
  19 %{
  20     private Token sym(int id) {
  21         return new Token(id, yychar, yychar+yylength(), yytext());
  22     }
  23 %}
  24
  25
  26 idChar         = [a-zA-Z0-9_]
  27 nonterminal    = [a-z]{idChar}*
  28 terminal       = [A-Z]{idChar}*
  29
  30 whitespace      = [ \n\r\t]+
  31 c_comment       = "//" [^\n\r]*
  32 cpp_comment     = "/*" ~"*/"
  33
  34 %%
  35
  36 <YYINITIAL> {
  37   {c_comment}     { }
  38   {cpp_comment}   { }
  39   "="             { return sym(GrammarTerminals.EQUALS); }
  40   "|"             { return sym(GrammarTerminals.BAR); }
  41   ";"             { return sym(GrammarTerminals.SEMICOLON); }
  42   "#"             { return sym(GrammarTerminals.HASH); }
  43   ","             { return sym(GrammarTerminals.COMMA); }
  44   "("             { return sym(GrammarTerminals.LPAREN); }
  45   ")"             { return sym(GrammarTerminals.RPAREN); }
  46   "*"             { return sym(GrammarTerminals.STAR); }
  47   "+"             { return sym(GrammarTerminals.PLUS); }
  48   "?"             { return sym(GrammarTerminals.OPTIONAL); }
  49   initial         { return sym(GrammarTerminals.INITIAL); }
  50   shift           { return sym(GrammarTerminals.SHIFT); }
  51   reduce          { return sym(GrammarTerminals.REDUCE); }
  52   {terminal}      { return sym(GrammarTerminals.TERMINAL); }
  53   {nonterminal}   { return sym(GrammarTerminals.NONTERMINAL); }
  54   {whitespace}    { }
  55   .               { throw new RuntimeException("Illegal character '" + yytext() + "'."); }
  56 }