tree bc40821f1a25a9b7db57e49a4e88be8df6341f64
parent 77d99491b26e61294af69e5cb209ea2a1a66a4a4
author Sovietaced <Sovietaced@gmail.com> 1403892837 -0700
committer Sovietaced <Sovietaced@gmail.com> 1403892837 -0700

use preconditions