reject

/*
 *  call-seq:
 *     hsh.reject {| key, value | block }  -> a_hash
 *
 *  Same as <code>Hash#delete_if</code>, but works on (and returns) a
 *  copy of the <i>hsh</i>. Equivalent to
 *  <code><i>hsh</i>.dup.delete_if</code>.
 *
 */

static VALUE
rb_hash_reject(hash)
    VALUE hash;
{
    return rb_hash_delete_if(rb_obj_dup(hash));
}