summaryrefslogtreecommitdiffstats
path: root/src/java/org/anarres/cpp/Macro.java
blob: c3574938f1df95903a7193e5bc7f35c5f2f49a3b (plain)
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
157
158
159
160
/*
 * Anarres C Preprocessor
 * Copyright (c) 2007-2008, Shevek
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied.  See the License for the specific language governing
 * permissions and limitations under the License.
 */

package org.anarres.cpp;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * A macro object.
 *
 * This encapsulates a name, an argument count, and a token stream
 * for replacement. The replacement token stream may contain the
 * extra tokens {@link Token#M_ARG} and {@link Token#M_STRING}.
 */
public class Macro {
	private String			name;
	/* It's an explicit decision to keep these around here. We don't
	 * need to; the argument token type is M_ARG and the value
	 * is the index. The strings themselves are only used in
	 * stringification of the macro, for debugging. */
	private List<String>	args;
	private boolean			variadic;
	private List<Token>		tokens;

	public Macro(String name) {
		this.name = name;
		this.args = null;
		this.variadic = false;
		this.tokens = new ArrayList<Token>();
	}

	/**
	 * Returns the name of this macro.
	 */
	public String getName() {
		return name;
	}

	/**
	 * Sets the arguments to this macro.
	 */
	public void setArgs(List<String> args) {
		this.args = args;
	}

	/**
	 * Returns true if this is a function-like macro.
	 */
	public boolean isFunctionLike() {
		return args != null;
	}

	/**
	 * Returns the number of arguments to this macro.
	 */
	public int getArgs() {
		return args.size();
	}

	/**
	 * Sets the variadic flag on this Macro.
	 */
	public void setVariadic(boolean b) {
		this.variadic = b;
	}

	/**
	 * Returns true if this is a variadic function-like macro.
	 */
	public boolean isVariadic() {
		return variadic;
	}

	/**
	 * Adds a token to the expansion of this macro.
	 */
	public void addToken(Token tok) {
		this.tokens.add(tok);
	}

	/**
	 * Adds a "paste" operator to the expansion of this macro.
	 *
	 * A paste operator causes the next token added to be pasted
	 * to the previous token when the macro is expanded.
	 * It is an error for a macro to end with a paste token.
	 */
	public void addPaste(Token tok) {
		/*
		 * Given: tok0 ## tok1
		 * We generate: M_PASTE, tok0, tok1
		 * This extends as per a stack language:
		 * tok0 ## tok1 ## tok2 ->
		 *   M_PASTE, tok0, M_PASTE, tok1, tok2
		 */
		this.tokens.add(tokens.size() - 1, tok);
	}

	/* pp */ List<Token> getTokens() {
		return tokens;
	}

	public String getText() {
		StringBuilder	buf = new StringBuilder();
		boolean			paste = false;
		for (int i = 0; i < tokens.size(); i++) {
			Token	tok = tokens.get(i);
			if (tok.getType() == Token.M_PASTE) {
				paste = true;
				continue;
			}
			else {
				buf.append(tok.getText());
			}
			if (paste) {
				buf.append(" #" + "# ");
				paste = false;
			}
			// buf.append(tokens.get(i));
		}
		return buf.toString();
	}

	public String toString() {
		StringBuilder	buf = new StringBuilder(name);
		if (args != null) {
			buf.append('(');
			Iterator<String>	it = args.iterator();
			while (it.hasNext()) {
				buf.append(it.next());
				if (it.hasNext())
					buf.append(", ");
				else if (isVariadic())
					buf.append("...");
			}
			buf.append(')');
		}
		if (!tokens.isEmpty()) {
			buf.append(" => ").append(getText());
		}
		return buf.toString();
	}

}