Ruby » Ruby master

/*

* call-seq:

* ary ^ other_ary -> new_ary

*

* Symmetric Difference --- Returns a new array containing the elements

* which appear in either +ary+ or +other_ary+, but not both. The order

* is preserved from the original array.

*

* It compares elements using their #hash and #eql? methods for efficiency.

*

* [1, 2, 3] ^ [2, 3, 4] # => [1, 4]

* %w[a b c] ^ %w[b c d d] # => ["a", "d"]

*

* If you need set-like behavior, see the library class Set.

*/

static VALUE

rb_ary_xor(VALUE ary1, VALUE ary2)

{

VALUE seen, result, ary3;

st_data_t elt;

long i;

ary2 = to_ary(ary2);

seen = rb_hash_new();

result = ary_make_hash(ary1);

for (i = 0; i < RARRAY_LEN(ary2); ++i) {

elt = (st_data_t)RARRAY_AREF(ary2, i);

if (st_lookup(RHASH_TBL_RAW(seen), elt, 0)) continue;

st_update(RHASH_TBL_RAW(seen), elt, ary_hash_orset, elt);

if (st_lookup(RHASH_TBL_RAW(result), elt, 0)) {

st_delete(RHASH_TBL_RAW(result), &elt, 0);

}

else {

st_update(RHASH_TBL_RAW(result), elt, ary_hash_orset, elt);

}

}

ary3 = rb_hash_values(result);

ary_recycle_hash(result);

ary_recycle_hash(seen);

return ary3;

}

rb_define_method(rb_cArray, "^", rb_ary_xor, 1);

def test_XOR

assert_equal(@cls[], @cls[] ^ @cls[])

assert_equal(@cls[1], @cls[1] ^ @cls[])

assert_equal(@cls[1], @cls[] ^ @cls[1])

assert_equal(@cls[], @cls[1] ^ @cls[1])

assert_equal(@cls[1,2], @cls[1] ^ @cls[2])

assert_equal(@cls[1,4], @cls[1,2,3] ^ @cls[2,3,4])

assert_equal(@cls[1,4], @cls[1,1,2,3] ^ @cls[2,3,4,4])

end