File: Parser.frame

package info (click to toggle)
coco-cs 20110419-5.2
  • links: PTS
  • area: main
  • in suites: bookworm, bullseye, sid
  • size: 256 kB
  • sloc: cs: 3,416; makefile: 55; sh: 1
file content (156 lines) | stat: -rwxr-xr-x 3,955 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
/*----------------------------------------------------------------------
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) {}
}