diff options
Diffstat (limited to 'array.c')
-rw-r--r-- | array.c | 29 |
1 files changed, 14 insertions, 15 deletions
@@ -4443,28 +4443,27 @@ static VALUE sym_random; static VALUE rb_ary_shuffle_bang(int argc, VALUE *argv, VALUE ary) { - VALUE *ptr, opts, *snap_ptr, randgen = rb_cRandom; - long i, snap_len; + VALUE opts, randgen = rb_cRandom; + long i, len; if (OPTHASH_GIVEN_P(opts)) { randgen = rb_hash_lookup2(opts, sym_random, randgen); } rb_check_arity(argc, 0, 0); rb_ary_modify(ary); - i = RARRAY_LEN(ary); - ptr = RARRAY_PTR(ary); - snap_len = i; - snap_ptr = ptr; - while (i) { - long j = RAND_UPTO(i); - VALUE tmp; - if (snap_len != RARRAY_LEN(ary) || snap_ptr != RARRAY_PTR(ary)) { - rb_raise(rb_eRuntimeError, "modified during shuffle"); + i = len = RARRAY_LEN(ary); + RARRAY_PTR_USE(ary, ptr, { + while (i) { + long j = RAND_UPTO(i); + VALUE tmp; + if (len != RARRAY_LEN(ary) || ptr != RARRAY_CONST_PTR(ary)) { + rb_raise(rb_eRuntimeError, "modified during shuffle"); + } + tmp = ptr[--i]; + ptr[i] = ptr[j]; + ptr[j] = tmp; } - tmp = ptr[--i]; - ptr[i] = ptr[j]; - ptr[j] = tmp; - } + }); /* WB: no new reference */ return ary; } |