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instance method
Comparable#clamp
[A, B] (A min, B max) -> (self | A | B)
[A] (::Range[A]) -> (self | A)
obj.clamp(min, max) → obj
obj.clamp(range) → obj
compar.c
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static VALUE
cmp_clamp(int argc, VALUE *argv, VALUE x)
{
VALUE min, max;
int c, excl = 0;
if (rb_scan_args(argc, argv, "11", &min, &max) == 1) {
VALUE range = min;
if (!rb_range_values(range, &min, &max, &excl)) {
rb_raise(rb_eTypeError, "wrong argument type %s (expected Range)",
rb_builtin_class_name(range));
}
if (!NIL_P(max)) {
if (excl) rb_raise(rb_eArgError, "cannot clamp with an exclusive range");
}
}
if (!NIL_P(min) && !NIL_P(max) && cmpint(min, max) > 0) {
rb_raise(rb_eArgError, "min argument must be less than or equal to max argument");
}
if (!NIL_P(min)) {
c = cmpint(x, min);
if (c == 0) return x;
if (c < 0) return min;
}
if (!NIL_P(max)) {
c = cmpint(x, max);
if (c > 0) return max;
}
return x;
}
In (min, max) form, returns min if obj <=> min is less than zero, max if obj <=> max is greater than zero, and obj otherwise.
Example
12.clamp(0, 100) #=> 12 523.clamp(0, 100) #=> 100 -3.123.clamp(0, 100) #=> 0 'd'.clamp('a', 'f') #=> 'd' 'z'.clamp('a', 'f') #=> 'f'
If min is nil, it is considered smaller than obj, and if max is nil, it is considered greater than obj.
Example
-20.clamp(0, nil) #=> 0 523.clamp(nil, 100) #=> 100
In (range) form, returns range.begin if obj <=> range.begin is less than zero, range.end if obj <=> range.end is greater than zero, and obj otherwise.
Example
12.clamp(0..100) #=> 12 523.clamp(0..100) #=> 100 -3.123.clamp(0..100) #=> 0 'd'.clamp('a'..'f') #=> 'd' 'z'.clamp('a'..'f') #=> 'f'
If range.begin is nil, it is considered smaller than obj, and if range.end is nil, it is considered greater than obj.
Example
-20.clamp(0..) #=> 0 523.clamp(..100) #=> 100
When range.end is excluded and not nil, an exception is raised.
Example
100.clamp(0...100) # ArgumentError