* array.c (rb_ary_rotate): new methods, Array#rotate! and

Array#rotate.  [ruby-dev:17194]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@26366 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
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nobu 2010-01-21 02:15:48 +00:00
Родитель 2cb9f63bab
Коммит 8a4c9b0b77
4 изменённых файлов: 163 добавлений и 8 удалений

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@ -1,4 +1,7 @@
Thu Jan 21 11:12:06 2010 Nobuyoshi Nakada <nobu@ruby-lang.org>
Thu Jan 21 11:15:46 2010 Nobuyoshi Nakada <nobu@ruby-lang.org>
* array.c (rb_ary_rotate): new methods, Array#rotate! and
Array#rotate. [ruby-dev:17194]
* array.c (rb_ary_reverse_m): copy directly.

2
NEWS
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@ -15,6 +15,8 @@ with all sufficient information, see the ChangeLog file.
* Array
* new method:
* Array#sort_by!
* Array#rotate!
* Array#rotate
* Dir
* new method:

117
array.c
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@ -1743,22 +1743,27 @@ rb_ary_to_ary_m(VALUE ary)
return ary;
}
static void
ary_reverse(p1, p2)
VALUE *p1, *p2;
{
while (p1 < p2) {
VALUE tmp = *p1;
*p1++ = *p2;
*p2-- = tmp;
}
}
VALUE
rb_ary_reverse(VALUE ary)
{
VALUE *p1, *p2;
VALUE tmp;
rb_ary_modify(ary);
if (RARRAY_LEN(ary) > 1) {
p1 = RARRAY_PTR(ary);
p2 = p1 + RARRAY_LEN(ary) - 1; /* points last item */
while (p1 < p2) {
tmp = *p1;
*p1++ = *p2;
*p2-- = tmp;
}
ary_reverse(p1, p2);
}
return ary;
}
@ -1804,6 +1809,102 @@ rb_ary_reverse_m(VALUE ary)
return dup;
}
static inline long
rotate_count(long cnt, long len)
{
return (cnt < 0) ? (len - (~cnt % len) - 1) : (cnt % len);
}
VALUE
rb_ary_rotate(VALUE ary, long cnt)
{
rb_ary_modify(ary);
if (cnt != 0) {
VALUE *ptr = RARRAY_PTR(ary);
long len = RARRAY_LEN(ary);
if (len > 0 && (cnt = rotate_count(cnt, len)) > 0) {
--len;
if (cnt < len) ary_reverse(ptr + cnt, ptr + len);
if (--cnt > 0) ary_reverse(ptr, ptr + cnt);
if (len > 0) ary_reverse(ptr, ptr + len);
return ary;
}
}
return Qnil;
}
/*
* call-seq:
* array.rotate!([cnt = 1]) -> array
*
* Rotates _self_ in place so that the element at +cnt+ comes first,
* and returns _self_. If +cnt+ is negative then it rotates in
* counter direction.
*
* a = [ "a", "b", "c", "d" ]
* a.rotate! #=> ["b", "c", "d", "a"]
* a #=> ["b", "c", "d", "a"]
* a.rotate!(2) #=> ["d", "a", "b", "c"]
* a.rotate!(-3) #=> ["a", "b", "c", "d"]
*/
static VALUE
rb_ary_rotate_bang(int argc, VALUE *argv, VALUE ary)
{
long n = 1;
switch (argc) {
case 1: n = NUM2LONG(argv[0]);
case 0: break;
default: rb_scan_args(argc, argv, "01", NULL);
}
rb_ary_rotate(ary, n);
return ary;
}
/*
* call-seq:
* array.rotate([n = 1]) -> an_array
*
* Returns new array by rotating _self_, whose first element is the
* element at +cnt+ in _self_. If +cnt+ is negative then it rotates
* in counter direction.
*
* a = [ "a", "b", "c", "d" ]
* a.rotate #=> ["b", "c", "d", "a"]
* a #=> ["a", "b", "c", "d"]
* a.rotate(2) #=> ["c", "d", "a", "b"]
* a.rotate(-3) #=> ["b", "c", "d", "a"]
*/
static VALUE
rb_ary_rotate_m(int argc, VALUE *argv, VALUE ary)
{
VALUE rotated, *ptr, *ptr2;
long len, cnt = 1;
switch (argc) {
case 1: cnt = NUM2LONG(argv[0]);
case 0: break;
default: rb_scan_args(argc, argv, "01", NULL);
}
len = RARRAY_LEN(ary);
rotated = rb_ary_dup_setup(ary);
if (len > 0) {
cnt = rotate_count(cnt, len);
ptr = RARRAY_PTR(ary);
ptr2 = RARRAY_PTR(rotated);
len -= cnt;
MEMCPY(ptr2, ptr + cnt, VALUE, len);
MEMCPY(ptr2 + len, ptr, VALUE, cnt);
}
return rotated;
}
struct ary_sort_data {
VALUE ary;
int opt_methods;
@ -4111,6 +4212,8 @@ Init_Array(void)
rb_define_method(rb_cArray, "join", rb_ary_join_m, -1);
rb_define_method(rb_cArray, "reverse", rb_ary_reverse_m, 0);
rb_define_method(rb_cArray, "reverse!", rb_ary_reverse_bang, 0);
rb_define_method(rb_cArray, "rotate", rb_ary_rotate_m, -1);
rb_define_method(rb_cArray, "rotate!", rb_ary_rotate_bang, -1);
rb_define_method(rb_cArray, "sort", rb_ary_sort, 0);
rb_define_method(rb_cArray, "sort!", rb_ary_sort_bang, 0);
rb_define_method(rb_cArray, "sort_by!", rb_ary_sort_by_bang, 0);

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@ -1767,4 +1767,51 @@ class TestArray < Test::Unit::TestCase
a.sort_by! {|x| -x }
assert_equal([5,4,3,2,1], a)
end
def test_rotate
a = [1,2,3,4,5].freeze
assert_equal([2,3,4,5,1], a.rotate)
assert_equal([5,1,2,3,4], a.rotate(-1))
assert_equal([3,4,5,1,2], a.rotate(2))
assert_equal([4,5,1,2,3], a.rotate(-2))
assert_equal([4,5,1,2,3], a.rotate(13))
assert_equal([3,4,5,1,2], a.rotate(-13))
a = [1].freeze
assert_equal([1], a.rotate)
assert_equal([1], a.rotate(2))
assert_equal([1], a.rotate(-4))
assert_equal([1], a.rotate(13))
assert_equal([1], a.rotate(-13))
a = [].freeze
assert_equal([], a.rotate)
assert_equal([], a.rotate(2))
assert_equal([], a.rotate(-4))
assert_equal([], a.rotate(13))
assert_equal([], a.rotate(-13))
end
def test_rotate!
a = [1,2,3,4,5]
assert_equal([2,3,4,5,1], a.rotate!)
assert_equal([2,3,4,5,1], a)
assert_equal([4,5,1,2,3], a.rotate!(2))
assert_equal([5,1,2,3,4], a.rotate!(-4))
assert_equal([3,4,5,1,2], a.rotate!(13))
assert_equal([5,1,2,3,4], a.rotate!(-13))
a = [1]
assert_equal([1], a.rotate!)
assert_equal([1], a.rotate!(2))
assert_equal([1], a.rotate!(-4))
assert_equal([1], a.rotate!(13))
assert_equal([1], a.rotate!(-13))
a = []
assert_equal([], a.rotate!)
assert_equal([], a.rotate!(2))
assert_equal([], a.rotate!(-4))
assert_equal([], a.rotate!(13))
assert_equal([], a.rotate!(-13))
a = [].freeze
e = assert_raise(RuntimeError) {a.rotate!}
assert_match(/can't modify frozen array/, e.message)
end
end