summaryrefslogtreecommitdiffstats
path: root/range.c
blob: a7f553be57d3e095fe17c92da8af1cc9cf86019b (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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
/**********************************************************************

  range.c -

  $Author$
  $Date$
  created at: Thu Aug 19 17:46:47 JST 1993

  Copyright (C) 1993-2003 Yukihiro Matsumoto

**********************************************************************/

#include "ruby.h"

VALUE rb_cRange;
static ID id_cmp, id_succ, id_beg, id_end, id_excl;

#define EXCL(r) RTEST(rb_ivar_get((r), id_excl))
#define SET_EXCL(r,v) rb_ivar_set((r), id_excl, (v) ? Qtrue : Qfalse)

static VALUE
range_failed()
{
    rb_raise(rb_eArgError, "bad value for range");
    return Qnil;		/* dummy */
}

static VALUE
range_check(args)
    VALUE *args;
{
    VALUE v;

    v = rb_funcall(args[0], id_cmp, 1, args[1]);
    if (NIL_P(v)) range_failed();
    return Qnil;
}

static void
range_init(range, beg, end, exclude_end)
    VALUE range, beg, end;
    int exclude_end;
{
    VALUE args[2];

    args[0] = beg;
    args[1] = end;
    
    if (!FIXNUM_P(beg) || !FIXNUM_P(end)) {
	rb_rescue(range_check, (VALUE)args, range_failed, 0);
    }

    SET_EXCL(range, exclude_end);
    rb_ivar_set(range, id_beg, beg);
    rb_ivar_set(range, id_end, end);
}

VALUE
rb_range_new(beg, end, exclude_end)
    VALUE beg, end;
    int exclude_end;
{
    VALUE range = rb_obj_alloc(rb_cRange);

    range_init(range, beg, end, exclude_end);
    return range;
}

static VALUE
range_initialize(argc, argv, range)
    int argc;
    VALUE *argv;
    VALUE range;
{
    VALUE beg, end, flags;
    
    rb_scan_args(argc, argv, "21", &beg, &end, &flags);
    /* Ranges are immutable, so that they should be initialized only once. */
    if (rb_ivar_defined(range, id_beg)) {
	rb_name_error(rb_intern("initialize"), "`initialize' called twice");
    }
    range_init(range, beg, end, RTEST(flags));
    return Qnil;
}

static VALUE
range_exclude_end_p(range)
    VALUE range;
{
    return EXCL(range) ? Qtrue : Qfalse;
}

static VALUE
range_eq(range, obj)
    VALUE range, obj;
{
    if (range == obj) return Qtrue;
    if (!rb_obj_is_instance_of(obj, rb_obj_class(range)))
	return Qfalse;

    if (!rb_equal(rb_ivar_get(range, id_beg), rb_ivar_get(obj, id_beg)))
	return Qfalse;
    if (!rb_equal(rb_ivar_get(range, id_end), rb_ivar_get(obj, id_end)))
	return Qfalse;

    if (EXCL(range) != EXCL(obj)) return Qfalse;

    return Qtrue;
}

static int
r_lt(a, b)
    VALUE a, b;
{
    VALUE r = rb_funcall(a, id_cmp, 1, b);

    if (NIL_P(r)) return Qfalse;
    if (rb_cmpint(r, a, b) < 0) return Qtrue;
    return Qfalse;
}

static int
r_le(a, b)
    VALUE a, b;
{
    VALUE r = rb_funcall(a, id_cmp, 1, b);

    if (NIL_P(r)) return Qfalse;
    if (rb_cmpint(r, a, b) <= 0) return Qtrue;
    return Qfalse;
}


static VALUE
range_eql(range, obj)
    VALUE range, obj;
{
    if (range == obj) return Qtrue;
    if (!rb_obj_is_instance_of(obj, rb_obj_class(range)))
	return Qfalse;

    if (!rb_eql(rb_ivar_get(range, id_beg), rb_ivar_get(obj, id_beg)))
	return Qfalse;
    if (!rb_eql(rb_ivar_get(range, id_end), rb_ivar_get(obj, id_end)))
	return Qfalse;

    if (EXCL(range) != EXCL(obj)) return Qfalse;

    return Qtrue;
}

static VALUE
range_hash(range)
    VALUE range;
{
    long hash = EXCL(range);
    VALUE v;

    v = rb_hash(rb_ivar_get(range, id_beg));
    hash ^= v << 1;
    v = rb_hash(rb_ivar_get(range, id_end));
    hash ^= v << 9;
    hash ^= EXCL(range) << 24;

    return LONG2FIX(hash);
}

static VALUE
str_step(args)
    VALUE *args;
{
    return rb_str_upto(args[0], args[1], EXCL(args[2]));
}

static VALUE
step_i(i, iter)
    VALUE i;
    long *iter;
{
    iter[0]--;
    if (iter[0] == 0) {
	rb_yield(i);
	iter[0] = iter[1];
    }
    return Qnil;
}

static void
range_each_func(range, func, v, e, arg)
    VALUE range;
    VALUE (*func) _((VALUE, void*));
    VALUE v, e;
    void *arg;
{
    if (EXCL(range)) {
	while (r_lt(v, e)) {
	    (*func)(v, arg);
	    v = rb_funcall(v, id_succ, 0, 0);
	}
    }
    else {
	while (r_le(v, e)) {
	    (*func)(v, arg);
	    v = rb_funcall(v, id_succ, 0, 0);
	}
    }
}

static VALUE
range_step(argc, argv, range)
    int argc;
    VALUE *argv;
    VALUE range;
{
    VALUE b, e, step;
    long unit;

    b = rb_ivar_get(range, id_beg);
    e = rb_ivar_get(range, id_end);
    if (rb_scan_args(argc, argv, "01", &step) == 0) {
	step = INT2FIX(1);
    }

    unit = NUM2LONG(step);
    if (unit < 0) {
	rb_raise(rb_eArgError, "step can't be negative");
    } 
    if (FIXNUM_P(b) && FIXNUM_P(e)) { /* fixnums are special */
	long end = FIX2LONG(e);
	long i;

	if (unit == 0) rb_raise(rb_eArgError, "step can't be 0");
	if (!EXCL(range)) end += 1;
	for (i=FIX2LONG(b); i<end; i+=unit) {
	    rb_yield(LONG2NUM(i));
	}
    }
    else {
	VALUE tmp = rb_check_string_type(b);

	if (!NIL_P(tmp)) {
	    VALUE args[5];
	    long iter[2];

	    b = tmp;
	    if (unit == 0) rb_raise(rb_eArgError, "step can't be 0");
	    args[0] = b; args[1] = e; args[2] = range;
	    iter[0] = 1; iter[1] = unit;
	    rb_iterate((VALUE(*)_((VALUE)))str_step, (VALUE)args, step_i, (VALUE)iter);
	}
	else if (rb_obj_is_kind_of(b, rb_cNumeric)) {
	    ID c = rb_intern(EXCL(range) ? "<" : "<=");

	    if (rb_equal(step, INT2FIX(0))) rb_raise(rb_eArgError, "step can't be 0");
	    while (RTEST(rb_funcall(b, c, 1, e))) {
		rb_yield(b);
		b = rb_funcall(b, '+', 1, step);
	    }
	}
	else {
	    long args[2];

	    if (unit == 0) rb_raise(rb_eArgError, "step can't be 0");
	    if (!rb_respond_to(b, id_succ)) {
		rb_raise(rb_eTypeError, "cannot iterate from %s",
			 rb_obj_classname(b));
	    }
	
	    args[0] = 1;
	    args[1] = unit;
	    range_each_func(range, step_i, b, e, args);
	}
    }
    return range;
}

static VALUE
each_i(v, arg)
    VALUE v;
    void *arg;
{
    return rb_yield(v);
}

static VALUE
range_each(range)
    VALUE range;
{
    VALUE beg, end;

    beg = rb_ivar_get(range, id_beg);
    end = rb_ivar_get(range, id_end);

    if (!rb_respond_to(beg, id_succ)) {
	rb_raise(rb_eTypeError, "cannot iterate from %s",
		 rb_obj_classname(beg));
    }
    if (FIXNUM_P(beg) && FIXNUM_P(end)) { /* fixnums are special */
	long lim = FIX2LONG(end);
	long i;

	if (!EXCL(range)) lim += 1;
	for (i=FIX2LONG(beg); i<lim; i++) {
	    rb_yield(LONG2NUM(i));
	}
    }
    else if (TYPE(beg) == T_STRING) {
	VALUE args[5];
	long iter[2];

	args[0] = beg; args[1] = end; args[2] = range;
	iter[0] = 1; iter[1] = 1;
	rb_iterate((VALUE(*)_((VALUE)))str_step, (VALUE)args, step_i, (VALUE)iter);
    }
    else {
	range_each_func(range, each_i, beg, end, NULL);
    }
    return range;
}

static VALUE
range_first(range)
    VALUE range;
{
    return rb_ivar_get(range, id_beg);
}

static VALUE
range_last(range)
    VALUE range;
{
    return rb_ivar_get(range, id_end);
}

VALUE
rb_range_beg_len(range, begp, lenp, len, err)
    VALUE range;
    long *begp, *lenp;
    long len;
    int err;
{
    long beg, end, b, e;

    if (!rb_obj_is_kind_of(range, rb_cRange)) return Qfalse;

    beg = b = NUM2LONG(rb_ivar_get(range, id_beg));
    end = e = NUM2LONG(rb_ivar_get(range, id_end));

    if (beg < 0) {
	beg += len;
	if (beg < 0) goto out_of_range;
    }
    if (err == 0 || err == 2) {
	if (beg > len) goto out_of_range;
	if (end > len)
	    end = len;
    }
    if (end < 0) end += len;
    if (!EXCL(range)) end++;	/* include end point */
    if (end < 0) goto out_of_range;
    len = end - beg;
    if (len < 0) goto out_of_range;

    *begp = beg;
    *lenp = len;
    return Qtrue;

  out_of_range:
    if (err) {
	rb_raise(rb_eRangeError, "%ld..%s%ld out of range",
		 b, EXCL(range)? "." : "", e);
    }
    return Qnil;
}

static VALUE
range_to_s(range)
    VALUE range;
{
    VALUE str, str2;

    str = rb_obj_as_string(rb_ivar_get(range, id_beg));
    str2 = rb_obj_as_string(rb_ivar_get(range, id_end));
    str = rb_str_dup(str);
    rb_str_cat(str, "...", EXCL(range)?3:2);
    rb_str_append(str, str2);
    OBJ_INFECT(str, str2);

    return str;
}

static VALUE
range_inspect(range)
    VALUE range;
{
    VALUE str, str2;

    str = rb_inspect(rb_ivar_get(range, id_beg));
    str2 = rb_inspect(rb_ivar_get(range, id_end));
    str = rb_str_dup(str);
    rb_str_cat(str, "...", EXCL(range)?3:2);
    rb_str_append(str, str2);
    OBJ_INFECT(str, str2);

    return str;
}

static void
member_i(v, args)
    VALUE v;
    VALUE *args;
{
    if (rb_equal(v, args[0])) {
	args[1] = Qtrue;
    }
}

static VALUE
range_member(range, val)
    VALUE range, val;
{
    VALUE beg, end;
    VALUE args[2];

    beg = rb_ivar_get(range, id_beg);
    end = rb_ivar_get(range, id_end);

    if (!rb_respond_to(beg, id_succ)) {
	rb_raise(rb_eTypeError, "cannot iterate from %s",
		 rb_obj_classname(beg));
    }
    args[0] = val;
    args[1] = Qfalse;
    range_each_func(range, member_i, beg, end, args);
    return args[1];
}

static VALUE
range_include(range, val)
    VALUE range, val;
{
    VALUE beg, end;

    beg = rb_ivar_get(range, id_beg);
    end = rb_ivar_get(range, id_end);
    if (r_le(beg, val)) {
	if (EXCL(range)) {
	    if (r_lt(val, end)) return Qtrue;
	}
	else {
	    if (r_le(val, end)) return Qtrue;
	}
    }
    return Qfalse;
}

void
Init_Range()
{
    rb_cRange = rb_define_class("Range", rb_cObject);
    rb_include_module(rb_cRange, rb_mEnumerable);
    rb_define_method(rb_cRange, "initialize", range_initialize, -1);
    rb_define_method(rb_cRange, "==", range_eq, 1);
    rb_define_method(rb_cRange, "===", range_include, 1);
    rb_define_method(rb_cRange, "eql?", range_eql, 1);
    rb_define_method(rb_cRange, "hash", range_hash, 0);
    rb_define_method(rb_cRange, "each", range_each, 0);
    rb_define_method(rb_cRange, "step", range_step, -1);
    rb_define_method(rb_cRange, "first", range_first, 0);
    rb_define_method(rb_cRange, "last", range_last, 0);
    rb_define_method(rb_cRange, "begin", range_first, 0);
    rb_define_method(rb_cRange, "end", range_last, 0);
    rb_define_method(rb_cRange, "to_s", range_to_s, 0);
    rb_define_method(rb_cRange, "inspect", range_inspect, 0);

    rb_define_method(rb_cRange, "exclude_end?", range_exclude_end_p, 0);

    rb_define_method(rb_cRange, "member?", range_member, 1);
    rb_define_method(rb_cRange, "include?", range_include, 1);

    id_cmp = rb_intern("<=>");
    id_succ = rb_intern("succ");
    id_beg = rb_intern("begin");
    id_end = rb_intern("end");
    id_excl = rb_intern("excl");
}