Ruby: compar.c Source File

Ruby 4.0.6p0 (2026-07-14 revision 03b6d3f8898a28604fe6cb00eae3226b821168f4)

compar.c
1/**********************************************************************
2
3 compar.c -
4
5 $Author$
6 created at: Thu Aug 26 14:39:48 JST 1993
7
8 Copyright (C) 1993-2007 Yukihiro Matsumoto
9
10**********************************************************************/
11
12#include "id.h"
13#include "internal.h"
14#include "internal/compar.h"
15#include "internal/error.h"
16#include "internal/vm.h"
17#include "ruby/ruby.h"
18
19 VALUE rb_mComparable;
20
21static VALUE
22rb_cmp(VALUE x, VALUE y)
23{
24 return rb_funcallv(x, idCmp, 1, &y);
25}
26
27void
28rb_cmperr(VALUE x, VALUE y)
29{
30 VALUE classname;
31
32 if (SPECIAL_CONST_P(y) || BUILTIN_TYPE(y) == T_FLOAT) {
33 classname = rb_inspect(y);
34 }
35 else {
36 classname = rb_obj_class(y);
37 }
38 rb_raise(rb_eArgError, "comparison of %"PRIsVALUE" with %"PRIsVALUE" failed",
39 rb_obj_class(x), classname);
40}
41
42static VALUE
43invcmp_recursive(VALUE x, VALUE y, int recursive)
44{
45 if (recursive) return Qnil;
46 return rb_cmp(y, x);
47}
48
49 VALUE
50rb_invcmp(VALUE x, VALUE y)
51{
52 VALUE invcmp = rb_exec_recursive(invcmp_recursive, x, y);
53 if (NIL_OR_UNDEF_P(invcmp)) {
54 return Qnil;
55 }
56 else {
57 int result = -rb_cmpint(invcmp, x, y);
58 return INT2FIX(result);
59 }
60}
61
62static VALUE
63cmp_eq_recursive(VALUE arg1, VALUE arg2, int recursive)
64{
65 if (recursive) return Qnil;
66 return rb_cmp(arg1, arg2);
67}
68
69/*
70 * call-seq:
71 * obj == other -> true or false
72 *
73 * Compares two objects based on the receiver's <code><=></code>
74 * method, returning true if it returns 0. Also returns true if
75 * _obj_ and _other_ are the same object.
76 */
77
78static VALUE
79cmp_equal(VALUE x, VALUE y)
80{
81 VALUE c;
82 if (x == y) return Qtrue;
83
84 c = rb_exec_recursive_paired_outer(cmp_eq_recursive, x, y, y);
85
86 if (NIL_P(c)) return Qfalse;
87 return RBOOL(rb_cmpint(c, x, y) == 0);
88}
89
90static int
91cmpint(VALUE x, VALUE y)
92{
93 return rb_cmpint(rb_cmp(x, y), x, y);
94}
95
96/*
97 * call-seq:
98 * obj > other -> true or false
99 *
100 * Compares two objects based on the receiver's <code><=></code>
101 * method, returning true if it returns a value greater than 0.
102 */
103
104static VALUE
105cmp_gt(VALUE x, VALUE y)
106{
107 return RBOOL(cmpint(x, y) > 0);
108}
109
110/*
111 * call-seq:
112 * obj >= other -> true or false
113 *
114 * Compares two objects based on the receiver's <code><=></code>
115 * method, returning true if it returns a value greater than or equal to 0.
116 */
117
118static VALUE
119cmp_ge(VALUE x, VALUE y)
120{
121 return RBOOL(cmpint(x, y) >= 0);
122}
123
124/*
125 * call-seq:
126 * self < other -> true or false
127 *
128 * Returns whether +self+ is "less than" +other+;
129 * equivalent to <tt>(self <=> other) < 0</tt>:
130 *
131 * 'foo' < 'foo' # => false
132 * 'foo' < 'food' # => true
133 *
134 */
135
136static VALUE
137cmp_lt(VALUE x, VALUE y)
138{
139 return RBOOL(cmpint(x, y) < 0);
140}
141
142/*
143 * call-seq:
144 * self <= other -> true or false
145 *
146 * Returns whether +self+ is "less than or equal to" +other+;
147 * equivalent to <tt>(self <=> other) <= 0</tt>:
148 *
149 * 'foo' <= 'foo' # => true
150 * 'foo' <= 'food' # => true
151 * 'food' <= 'foo' # => false
152 *
153 */
154
155static VALUE
156cmp_le(VALUE x, VALUE y)
157{
158 return RBOOL(cmpint(x, y) <= 0);
159}
160
161/*
162 * call-seq:
163 * obj.between?(min, max) -> true or false
164 *
165 * Returns <code>false</code> if _obj_ <code><=></code> _min_ is less
166 * than zero or if _obj_ <code><=></code> _max_ is greater than zero,
167 * <code>true</code> otherwise.
168 *
169 * 3.between?(1, 5) #=> true
170 * 6.between?(1, 5) #=> false
171 * 'cat'.between?('ant', 'dog') #=> true
172 * 'gnu'.between?('ant', 'dog') #=> false
173 *
174 */
175
176static VALUE
177cmp_between(VALUE x, VALUE min, VALUE max)
178{
179 return RBOOL((cmpint(x, min) >= 0 && cmpint(x, max) <= 0));
180}
181
182/*
183 * call-seq:
184 * obj.clamp(min, max) -> obj
185 * obj.clamp(range) -> obj
186 *
187 * In <code>(min, max)</code> form, returns _min_ if _obj_
188 * <code><=></code> _min_ is less than zero, _max_ if _obj_
189 * <code><=></code> _max_ is greater than zero, and _obj_
190 * otherwise.
191 *
192 * 12.clamp(0, 100) #=> 12
193 * 523.clamp(0, 100) #=> 100
194 * -3.123.clamp(0, 100) #=> 0
195 *
196 * 'd'.clamp('a', 'f') #=> 'd'
197 * 'z'.clamp('a', 'f') #=> 'f'
198 *
199 * If _min_ is +nil+, it is considered smaller than _obj_,
200 * and if _max_ is +nil+, it is considered greater than _obj_.
201 *
202 * -20.clamp(0, nil) #=> 0
203 * 523.clamp(nil, 100) #=> 100
204 *
205 * In <code>(range)</code> form, returns _range.begin_ if _obj_
206 * <code><=></code> _range.begin_ is less than zero, _range.end_
207 * if _obj_ <code><=></code> _range.end_ is greater than zero, and
208 * _obj_ otherwise.
209 *
210 * 12.clamp(0..100) #=> 12
211 * 523.clamp(0..100) #=> 100
212 * -3.123.clamp(0..100) #=> 0
213 *
214 * 'd'.clamp('a'..'f') #=> 'd'
215 * 'z'.clamp('a'..'f') #=> 'f'
216 *
217 * If _range.begin_ is +nil+, it is considered smaller than _obj_,
218 * and if _range.end_ is +nil+, it is considered greater than
219 * _obj_.
220 *
221 * -20.clamp(0..) #=> 0
222 * 523.clamp(..100) #=> 100
223 *
224 * When _range.end_ is excluded and not +nil+, an exception is
225 * raised.
226 *
227 * 100.clamp(0...100) # ArgumentError
228 */
229
230static VALUE
231cmp_clamp(int argc, VALUE *argv, VALUE x)
232{
233 VALUE min, max;
234 int c, excl = 0;
235
236 if (rb_scan_args(argc, argv, "11", &min, &max) == 1) {
237 VALUE range = min;
238 if (!rb_range_values(range, &min, &max, &excl)) {
239 rb_raise(rb_eTypeError, "wrong argument type %s (expected Range)",
240 rb_builtin_class_name(range));
241 }
242 if (!NIL_P(max)) {
243 if (excl) rb_raise(rb_eArgError, "cannot clamp with an exclusive range");
244 }
245 }
246 if (!NIL_P(min) && !NIL_P(max) && cmpint(min, max) > 0) {
247 rb_raise(rb_eArgError, "min argument must be less than or equal to max argument");
248 }
249
250 if (!NIL_P(min)) {
251 c = cmpint(x, min);
252 if (c == 0) return x;
253 if (c < 0) return min;
254 }
255 if (!NIL_P(max)) {
256 c = cmpint(x, max);
257 if (c > 0) return max;
258 }
259 return x;
260}
261
262/*
263 * The Comparable mixin is used by classes whose objects may be
264 * ordered. The class must define the <code><=></code> operator,
265 * which compares the receiver against another object, returning a
266 * value less than 0, returning 0, or returning a value greater than 0,
267 * depending on whether the receiver is less than, equal to,
268 * or greater than the other object. If the other object is not
269 * comparable then the <code><=></code> operator should return +nil+.
270 * Comparable uses <code><=></code> to implement the conventional
271 * comparison operators (<code><</code>, <code><=</code>,
272 * <code>==</code>, <code>>=</code>, and <code>></code>) and the
273 * method <code>between?</code>.
274 *
275 * class StringSorter
276 * include Comparable
277 *
278 * attr :str
279 * def <=>(other)
280 * str.size <=> other.str.size
281 * end
282 *
283 * def initialize(str)
284 * @str = str
285 * end
286 *
287 * def inspect
288 * @str
289 * end
290 * end
291 *
292 * s1 = StringSorter.new("Z")
293 * s2 = StringSorter.new("YY")
294 * s3 = StringSorter.new("XXX")
295 * s4 = StringSorter.new("WWWW")
296 * s5 = StringSorter.new("VVVVV")
297 *
298 * s1 < s2 #=> true
299 * s4.between?(s1, s3) #=> false
300 * s4.between?(s3, s5) #=> true
301 * [ s3, s2, s5, s4, s1 ].sort #=> [Z, YY, XXX, WWWW, VVVVV]
302 *
303 * == What's Here
304 *
305 * Module \Comparable provides these methods, all of which use method <tt>#<=></tt>:
306 *
307 * - #<: Returns whether +self+ is less than the given object.
308 * - #<=: Returns whether +self+ is less than or equal to the given object.
309 * - #==: Returns whether +self+ is equal to the given object.
310 * - #>: Returns whether +self+ is greater than the given object.
311 * - #>=: Returns whether +self+ is greater than or equal to the given object.
312 * - #between?: Returns +true+ if +self+ is between two given objects.
313 * - #clamp: For given objects +min+ and +max+, or range <tt>(min..max)</tt>, returns:
314 *
315 * - +min+ if <tt>(self <=> min) < 0</tt>.
316 * - +max+ if <tt>(self <=> max) > 0</tt>.
317 * - +self+ otherwise.
318 *
319 */
320
321void
322Init_Comparable(void)
323{
324 rb_mComparable = rb_define_module("Comparable");
325 rb_define_method(rb_mComparable, "==", cmp_equal, 1);
326 rb_define_method(rb_mComparable, ">", cmp_gt, 1);
327 rb_define_method(rb_mComparable, ">=", cmp_ge, 1);
328 rb_define_method(rb_mComparable, "<", cmp_lt, 1);
329 rb_define_method(rb_mComparable, "<=", cmp_le, 1);
330 rb_define_method(rb_mComparable, "between?", cmp_between, 2);
331 rb_define_method(rb_mComparable, "clamp", cmp_clamp, -1);
332}
rb_define_method
#define rb_define_method(klass, mid, func, arity)
Defines klass#mid.
Definition cxxanyargs.hpp:670
rb_define_module
VALUE rb_define_module(const char *name)
Defines a top-level module.
Definition class.c:1590
rb_scan_args
int rb_scan_args(int argc, const VALUE *argv, const char *fmt,...)
Retrieves argument from argc and argv to given VALUE references according to the format string.
Definition class.c:3132
INT2FIX
#define INT2FIX
Old name of RB_INT2FIX.
Definition long.h:48
T_FLOAT
#define T_FLOAT
Old name of RUBY_T_FLOAT.
Definition value_type.h:64
SPECIAL_CONST_P
#define SPECIAL_CONST_P
Old name of RB_SPECIAL_CONST_P.
Definition special_consts.h:56
Qtrue
#define Qtrue
Old name of RUBY_Qtrue.
Definition special_consts.h:61
Qnil
#define Qnil
Old name of RUBY_Qnil.
Definition special_consts.h:60
Qfalse
#define Qfalse
Old name of RUBY_Qfalse.
Definition special_consts.h:59
NIL_P
#define NIL_P
Old name of RB_NIL_P.
Definition special_consts.h:55
BUILTIN_TYPE
#define BUILTIN_TYPE
Old name of RB_BUILTIN_TYPE.
Definition value_type.h:85
rb_eTypeError
VALUE rb_eTypeError
TypeError exception.
Definition error.c:1431
rb_obj_class
VALUE rb_obj_class(VALUE obj)
Queries the class of an object.
Definition object.c:264
rb_inspect
VALUE rb_inspect(VALUE obj)
Generates a human-readable textual representation of the given object.
Definition object.c:686
rb_mComparable
VALUE rb_mComparable
Comparable module.
Definition compar.c:19
rb_range_values
int rb_range_values(VALUE range, VALUE *begp, VALUE *endp, int *exclp)
Deconstructs a range into its components.
Definition range.c:1862
rb_exec_recursive
VALUE rb_exec_recursive(VALUE(*f)(VALUE g, VALUE h, int r), VALUE g, VALUE h)
"Recursion" API entry point.
Definition thread.c:5606
rb_exec_recursive_paired_outer
VALUE rb_exec_recursive_paired_outer(VALUE(*f)(VALUE g, VALUE h, int r), VALUE g, VALUE p, VALUE h)
Identical to rb_exec_recursive_outer(), except it checks for the recursion on the ordered pair of { g...
Definition thread.c:5647
ruby.h
VALUE
uintptr_t VALUE
Type that represents a Ruby object.
Definition value.h:40