source: branches/HeuristicLab.Problems.GPDL/CocoR/Parser.frame

/*----------------------------------------------------------------------
Compiler Generator Coco/R,
Copyright (c) 1990, 2004 Hanspeter Moessenboeck, University of Linz
extended by M. Loeberbauer & A. Woess, Univ. of Linz
with improvements by Pat Terry, Rhodes University

This program is free software; you can redistribute it and/or modify it 
under the terms of the GNU General Public License as published by the 
Free Software Foundation; either version 2, or (at your option) any 
later version.

This program is distributed in the hope that it will be useful, but 
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License 
for more details.

You should have received a copy of the GNU General Public License along 
with this program; if not, write to the Free Software Foundation, Inc., 
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

As an exception, it is allowed to write an extension of Coco/R that is
used as a plugin in non-free software.

If not otherwise stated, any source code generated by Coco/R (other than 
Coco/R itself) does not fall under the GNU General Public License.
----------------------------------------------------------------------*/
-->begin
using System;

-->namespace

public class Parser {
-->constants
  const bool T = true;
  const bool x = false;
  const int minErrDist = 2;
  
  public Scanner scanner;
  public Errors  errors;

  public Token t;    // last recognized token
  public Token la;   // lookahead token
  int errDist = minErrDist;

-->declarations

  public Parser(Scanner scanner) {
    this.scanner = scanner;
    errors = new Errors();
  }

  void SynErr (int n) {
    if (errDist >= minErrDist) errors.SynErr(la.line, la.col, n);
    errDist = 0;
  }

  public void SemErr (string msg) {
    if (errDist >= minErrDist) errors.SemErr(t.line, t.col, msg);
    errDist = 0;
  }
  
  void Get () {
    for (;;) {
      t = la;
      la = scanner.Scan();
      if (la.kind <= maxT) { ++errDist; break; }
-->pragmas
      la = t;
    }
  }
  
  void Expect (int n) {
    if (la.kind==n) Get(); else { SynErr(n); }
  }
  
  bool StartOf (int s) {
    return set[s, la.kind];
  }
  
  void ExpectWeak (int n, int follow) {
    if (la.kind == n) Get();
    else {
      SynErr(n);
      while (!StartOf(follow)) Get();
    }
  }


  bool WeakSeparator(int n, int syFol, int repFol) {
    int kind = la.kind;
    if (kind == n) {Get(); return true;}
    else if (StartOf(repFol)) {return false;}
    else {
      SynErr(n);
      while (!(set[syFol, kind] || set[repFol, kind] || set[0, kind])) {
        Get();
        kind = la.kind;
      }
      return StartOf(syFol);
    }
  }

  
-->productions

  public void Parse() {
    la = new Token();
    la.val = "";    
    Get();
-->parseRoot
  }
  
  static readonly bool[,] set = {
-->initialization
  };
} // end Parser


public class Errors {
  public int count = 0;                                    // number of errors detected
  public System.IO.TextWriter errorStream = Console.Out;   // error messages go to this stream
  public string errMsgFormat = "-- line {0} col {1}: {2}"; // 0=line, 1=column, 2=text

  public virtual void SynErr (int line, int col, int n) {
    string s;
    switch (n) {
-->errors
      default: s = "error " + n; break;
    }
    errorStream.WriteLine(errMsgFormat, line, col, s);
    count++;
  }

  public virtual void SemErr (int line, int col, string s) {
    errorStream.WriteLine(errMsgFormat, line, col, s);
    count++;
  }
  
  public virtual void SemErr (string s) {
    errorStream.WriteLine(s);
    count++;
  }
  
  public virtual void Warning (int line, int col, string s) {
    errorStream.WriteLine(errMsgFormat, line, col, s);
  }
  
  public virtual void Warning(string s) {
    errorStream.WriteLine(s);
  }
} // Errors


public class FatalError: Exception {
  public FatalError(string m): base(m) {}
}