www.pudn.com > LexYaccProgs.zip > YACCLIB.PAS

 
unit YaccLib; 
 
(* Yacc Library Unit for TP Yacc Version 3.0, 6-17-91 AG *) 
 
interface 
 
const yymaxdepth = 1024; 
  (* default stack size of parser *) 
 
type YYSType = Integer; 
  (* default value type, may be redefined in Yacc output file *) 
 
var 
 
yychar   : Integer; (* current lookahead character *) 
yynerrs  : Integer; (* current number of syntax errors reported by the 
                       parser *) 
yydebug  : Boolean; (* set to true to enable debugging output of parser *) 
 
procedure yyerror ( msg : String ); 
  (* error message printing routine used by the parser *) 
 
procedure yyclearin; 
  (* delete the current lookahead token *) 
 
procedure yyaccept; 
  (* trigger accept action of the parser; yyparse accepts returning 0, as if 
     it reached end of input *) 
 
procedure yyabort; 
  (* like yyaccept, but causes parser to return with value 1, as if an 
     unrecoverable syntax error had been encountered *) 
 
procedure yyerrlab; 
  (* causes error recovery to be started, as if a syntax error had been 
     encountered *) 
 
procedure yyerrok; 
  (* when in error mode, resets the parser to its normal mode of 
     operation *) 
 
(* Flags used internally by the parser routine: *) 
 
var 
 
yyflag    : ( yyfnone, yyfaccept, yyfabort, yyferror ); 
yyerrflag : Integer; 
 
implementation 
 
procedure yyerror ( msg : String ); 
  begin 
    writeln(msg); 
  end(*yyerrmsg*); 
 
procedure yyclearin; 
  begin 
    yychar := -1; 
  end(*yyclearin*); 
 
procedure yyaccept; 
  begin 
    yyflag := yyfaccept; 
  end(*yyaccept*); 
 
procedure yyabort; 
  begin 
    yyflag := yyfabort; 
  end(*yyabort*); 
 
procedure yyerrlab; 
  begin 
    yyflag := yyferror; 
  end(*yyerrlab*); 
 
procedure yyerrok; 
  begin 
    yyerrflag := 0; 
  end(*yyerrork*); 
 
end(*YaccLib*).