enum.c:484
static VALUE
enum_member(obj, val)
    VALUE obj, val;
{
    VALUE result;
    NODE *memo = rb_node_newnode(NODE_MEMO, val, Qfalse, 0);

    rb_iterate(rb_each, obj, member_i, (VALUE)memo);
    result = memo->u2.value;
    rb_gc_force_recycle((VALUE)memo);
    return result;
}
