/*
 * call-seq:
 *   rng.hash    => fixnum
 *
 * Generate a hash value such that two ranges with the same start and
 * end points, and the same value for the "exclude end" flag, generate
 * the same hash value.
 */

static VALUE
range_hash(range)
    VALUE range;
{
    long hash = EXCL(range);
    VALUE v;

    v = rb_hash(rb_ivar_get(range, id_beg));
    hash ^= v << 1;
    v = rb_hash(rb_ivar_get(range, id_end));
    hash ^= v << 9;
    hash ^= EXCL(range) << 24;

    return LONG2FIX(hash);
}