[9724] | 1 | /*----------------------------------------------------------------------
|
---|
| 2 | Compiler Generator Coco/R,
|
---|
| 3 | Copyright (c) 1990, 2004 Hanspeter Moessenboeck, University of Linz
|
---|
| 4 | extended by M. Loeberbauer & A. Woess, Univ. of Linz
|
---|
| 5 | with improvements by Pat Terry, Rhodes University
|
---|
| 6 |
|
---|
| 7 | This program is free software; you can redistribute it and/or modify it
|
---|
| 8 | under the terms of the GNU General Public License as published by the
|
---|
| 9 | Free Software Foundation; either version 2, or (at your option) any
|
---|
| 10 | later version.
|
---|
| 11 |
|
---|
| 12 | This program is distributed in the hope that it will be useful, but
|
---|
| 13 | WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
---|
| 14 | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
---|
| 15 | for more details.
|
---|
| 16 |
|
---|
| 17 | You should have received a copy of the GNU General Public License along
|
---|
| 18 | with this program; if not, write to the Free Software Foundation, Inc.,
|
---|
| 19 | 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
---|
| 20 |
|
---|
| 21 | As an exception, it is allowed to write an extension of Coco/R that is
|
---|
| 22 | used as a plugin in non-free software.
|
---|
| 23 |
|
---|
| 24 | If not otherwise stated, any source code generated by Coco/R (other than
|
---|
| 25 | Coco/R itself) does not fall under the GNU General Public License.
|
---|
| 26 | ----------------------------------------------------------------------*/
|
---|
| 27 | -->begin
|
---|
| 28 | using System;
|
---|
| 29 |
|
---|
| 30 | -->namespace
|
---|
| 31 |
|
---|
| 32 | public class Parser {
|
---|
| 33 | -->constants
|
---|
| 34 | const bool T = true;
|
---|
| 35 | const bool x = false;
|
---|
| 36 | const int minErrDist = 2;
|
---|
| 37 |
|
---|
| 38 | public Scanner scanner;
|
---|
| 39 | public Errors errors;
|
---|
| 40 |
|
---|
| 41 | public Token t; // last recognized token
|
---|
| 42 | public Token la; // lookahead token
|
---|
| 43 | int errDist = minErrDist;
|
---|
| 44 |
|
---|
| 45 | -->declarations
|
---|
| 46 |
|
---|
| 47 | public Parser(Scanner scanner) {
|
---|
| 48 | this.scanner = scanner;
|
---|
| 49 | errors = new Errors();
|
---|
| 50 | }
|
---|
| 51 |
|
---|
| 52 | void SynErr (int n) {
|
---|
| 53 | if (errDist >= minErrDist) errors.SynErr(la.line, la.col, n);
|
---|
| 54 | errDist = 0;
|
---|
| 55 | }
|
---|
| 56 |
|
---|
| 57 | public void SemErr (string msg) {
|
---|
| 58 | if (errDist >= minErrDist) errors.SemErr(t.line, t.col, msg);
|
---|
| 59 | errDist = 0;
|
---|
| 60 | }
|
---|
| 61 |
|
---|
| 62 | void Get () {
|
---|
| 63 | for (;;) {
|
---|
| 64 | t = la;
|
---|
| 65 | la = scanner.Scan();
|
---|
| 66 | if (la.kind <= maxT) { ++errDist; break; }
|
---|
| 67 | -->pragmas
|
---|
| 68 | la = t;
|
---|
| 69 | }
|
---|
| 70 | }
|
---|
| 71 |
|
---|
| 72 | void Expect (int n) {
|
---|
| 73 | if (la.kind==n) Get(); else { SynErr(n); }
|
---|
| 74 | }
|
---|
| 75 |
|
---|
| 76 | bool StartOf (int s) {
|
---|
| 77 | return set[s, la.kind];
|
---|
| 78 | }
|
---|
| 79 |
|
---|
| 80 | void ExpectWeak (int n, int follow) {
|
---|
| 81 | if (la.kind == n) Get();
|
---|
| 82 | else {
|
---|
| 83 | SynErr(n);
|
---|
| 84 | while (!StartOf(follow)) Get();
|
---|
| 85 | }
|
---|
| 86 | }
|
---|
| 87 |
|
---|
| 88 |
|
---|
| 89 | bool WeakSeparator(int n, int syFol, int repFol) {
|
---|
| 90 | int kind = la.kind;
|
---|
| 91 | if (kind == n) {Get(); return true;}
|
---|
| 92 | else if (StartOf(repFol)) {return false;}
|
---|
| 93 | else {
|
---|
| 94 | SynErr(n);
|
---|
| 95 | while (!(set[syFol, kind] || set[repFol, kind] || set[0, kind])) {
|
---|
| 96 | Get();
|
---|
| 97 | kind = la.kind;
|
---|
| 98 | }
|
---|
| 99 | return StartOf(syFol);
|
---|
| 100 | }
|
---|
| 101 | }
|
---|
| 102 |
|
---|
| 103 |
|
---|
| 104 | -->productions
|
---|
| 105 |
|
---|
| 106 | public void Parse() {
|
---|
| 107 | la = new Token();
|
---|
| 108 | la.val = "";
|
---|
| 109 | Get();
|
---|
| 110 | -->parseRoot
|
---|
| 111 | }
|
---|
| 112 |
|
---|
| 113 | static readonly bool[,] set = {
|
---|
| 114 | -->initialization
|
---|
| 115 | };
|
---|
| 116 | } // end Parser
|
---|
| 117 |
|
---|
| 118 |
|
---|
| 119 | public class Errors {
|
---|
| 120 | public int count = 0; // number of errors detected
|
---|
| 121 | public System.IO.TextWriter errorStream = Console.Out; // error messages go to this stream
|
---|
| 122 | public string errMsgFormat = "-- line {0} col {1}: {2}"; // 0=line, 1=column, 2=text
|
---|
| 123 |
|
---|
| 124 | public virtual void SynErr (int line, int col, int n) {
|
---|
| 125 | string s;
|
---|
| 126 | switch (n) {
|
---|
| 127 | -->errors
|
---|
| 128 | default: s = "error " + n; break;
|
---|
| 129 | }
|
---|
| 130 | errorStream.WriteLine(errMsgFormat, line, col, s);
|
---|
| 131 | count++;
|
---|
| 132 | }
|
---|
| 133 |
|
---|
| 134 | public virtual void SemErr (int line, int col, string s) {
|
---|
| 135 | errorStream.WriteLine(errMsgFormat, line, col, s);
|
---|
| 136 | count++;
|
---|
| 137 | }
|
---|
| 138 |
|
---|
| 139 | public virtual void SemErr (string s) {
|
---|
| 140 | errorStream.WriteLine(s);
|
---|
| 141 | count++;
|
---|
| 142 | }
|
---|
| 143 |
|
---|
| 144 | public virtual void Warning (int line, int col, string s) {
|
---|
| 145 | errorStream.WriteLine(errMsgFormat, line, col, s);
|
---|
| 146 | }
|
---|
| 147 |
|
---|
| 148 | public virtual void Warning(string s) {
|
---|
| 149 | errorStream.WriteLine(s);
|
---|
| 150 | }
|
---|
| 151 | } // Errors
|
---|
| 152 |
|
---|
| 153 |
|
---|
| 154 | public class FatalError: Exception {
|
---|
| 155 | public FatalError(string m): base(m) {}
|
---|
| 156 | }
|
---|