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1
4 package gnu.expr;
5 import gnu.mapping.*;
6 import gnu.bytecode.Type;
7
8
9
10 public class GenericProc extends MethodProc
11 {
12 protected MethodProc[] methods;
13 int count;
14 int minArgs;
15 int maxArgs;
16
17 public GenericProc (String  name)
18 {
19 setName(name);
20 }
21
22 public GenericProc ()
23 {
24 }
25
26 public int numArgs()
27 {
28 return minArgs | (maxArgs << 12);
29 }
30
31 protected synchronized void add (MethodProc[] procs)
32 {
33 int n = procs.length;
34 if (methods == null)
35 methods = new MethodProc[n];
36 for (int i = 0; i < n; i++)
37 add(procs[i]);
38 }
39
40 public synchronized void add(MethodProc method)
41 {
42 if (methods == null)
43 methods = new MethodProc[8];
44 else if (count >= methods.length)
45 {
46 MethodProc[] copy = new MethodProc[2 * methods.length];
47 System.arraycopy(methods, 0, copy, 0, count);
48 methods = copy;
49 }
50
51 int i;
52 for (i = 0; i < count; i++)
53 {
54 MethodProc best = MethodProc.mostSpecific(method, methods[i]);
55 if (best == method)
56 break;
57 }
58 if (i < count)
59 System.arraycopy(methods, i, methods, i + 1, count - i);
60 methods[i] = method;
61
62 int n = method.minArgs();
63 if (n < minArgs || count==0)
64 minArgs = n;
65 n = method.maxArgs();
66 if (n == -1 || n > maxArgs)
67 maxArgs = n;
68 count++;
69 }
70
71
89
90 public Object applyN(Object [] args) throws Throwable
91 {
92 if (count == 1)
93 return methods[0].applyN(args);
94 checkArgCount(this, args.length);
95 CallContext ctx = CallContext.getInstance();
96 for (int i = 0; i < count; i++)
97 {
98 MethodProc method = methods[i];
99 int m = method.matchN(args, ctx);
100 if (m == 0)
101 return ctx.runUntilValue();
102 }
103 throw new WrongType(this, WrongType.ARG_UNKNOWN, null);
104 }
105
106 public int isApplicable(Type[] args)
107 {
108 int best = -1;
109 for (int i = count; --i >= 0; )
110 {
111 MethodProc method = methods[i];
112 int result = method.isApplicable(args);
113 if (result == 1)
114 return 1;
115 if (result == 0)
116 best = 0;
117 }
118 return best;
119 }
120
121 public int match0 (CallContext ctx)
122 {
123 if (count == 1)
124 return methods[0].match0(ctx);
125 for (int i = 0; i < count; i++)
126 {
127 MethodProc method = methods[i];
128 int code = method.match0(ctx);
129 if (code == 0)
130 return 0;
131 }
132 ctx.proc = null;
133 return NO_MATCH;
134 }
135
136 public int match1 (Object arg1, CallContext ctx)
137 {
138 if (count == 1)
139 return methods[0].match1(arg1, ctx);
140 for (int i = 0; i < count; i++)
141 {
142 MethodProc method = methods[i];
143 int code = method.match1(arg1, ctx);
144 if (code == 0)
145 return 0;
146 }
147 ctx.proc = null;
148 return NO_MATCH;
149 }
150
151 public int match2 (Object arg1, Object arg2, CallContext ctx)
152 {
153 if (count == 1)
154 return methods[0].match2(arg1, arg2, ctx);
155 for (int i = 0; i < count; i++)
156 {
157 MethodProc method = methods[i];
158 int code = method.match2(arg1, arg2, ctx);
159 if (code == 0)
160 return 0;
161 }
162 ctx.proc = null;
163 return NO_MATCH;
164 }
165
166 public int match3 (Object arg1, Object arg2, Object arg3, CallContext ctx)
167 {
168 if (count == 1)
169 return methods[0].match3(arg1, arg2, arg3, ctx);
170 for (int i = 0; i < count; i++)
171 {
172 MethodProc method = methods[i];
173 int code = method.match3(arg1, arg2, arg3, ctx);
174 if (code == 0)
175 return 0;
176 }
177 ctx.proc = null;
178 return NO_MATCH;
179 }
180
181 public int match4 (Object arg1, Object arg2, Object arg3, Object arg4,
182 CallContext ctx)
183 {
184 if (count == 1)
185 return methods[0].match4(arg1, arg2, arg3, arg4, ctx);
186 for (int i = 0; i < count; i++)
187 {
188 MethodProc method = methods[i];
189 int code = method.match4(arg1, arg2, arg3, arg4, ctx);
190 if (code == 0)
191 return 0;
192 }
193 ctx.proc = null;
194 return NO_MATCH;
195 }
196
197 public int matchN (Object [] args, CallContext ctx)
198 {
199 if (count == 1)
200 return methods[0].matchN(args, ctx);
201 int alen = args.length;
202 Type[] atypes = new Type[alen];
203 Language language = Language.getDefaultLanguage();
204 for (int j = 0; j < alen; j++)
208 {
209 Object arg = args[j];
210 Type atype;
211 if (arg == null)
212 atype = Type.nullType;
213 else
214 {
215 Class aclass = arg.getClass();
216 if (language != null)
217 atype = language.getTypeFor(aclass);
218 else
219 atype = Type.make(aclass);
220 }
221 atypes[j] = atype;
222 }
223 int[] codes = new int[count];
224 int defCount = 0;
225 int maybeCount = 0;
226 int bestIndex = -1;
227 for (int i = 0; i < count; i++)
228 {
229 int code = methods[i].isApplicable(atypes);
230 if (defCount == 0 && code >= 0)
231 bestIndex = i;
232 if (code > 0)
233 defCount++;
234 else if (code == 0)
235 maybeCount++;
236 codes[i] = code;
237 }
238 if (defCount == 1 || (defCount == 0 && maybeCount == 1))
239 return methods[bestIndex].matchN(args, ctx);
240 for (int i = 0; i < count; i++)
241 {
242 int code = codes[i];
243 if (code < 0 || (code == 0 && defCount > 0))
244 continue;
245 MethodProc method = methods[i];
246 code = method.matchN(args, ctx);
247 if (code == 0)
248 return 0;
249 }
250 ctx.proc = null;
251 return NO_MATCH;
252 }
253
254 public final void setProperties (Object [] args)
255 {
256 int alen = args.length;
257 for (int i = 0; i < alen; i++)
258 {
259 Object arg = args[i];
260 if (arg instanceof Keyword)
261 {
262 String name = ((Keyword) arg).getName();
263 Object value = args[++i];
264 if (name == "name")
265 setName(value.toString());
266 else if (name == "method")
267 add((MethodProc) value);
268 else
269 setProperty(name, value);
270 }
271 else
272 add((MethodProc) arg);
273 }
274 }
275
276
277 public static GenericProc make (Object [] args)
278 {
279 GenericProc result = new GenericProc();
280 result.setProperties(args);
281 return result;
282 }
283 }
284 |
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