Undefined variables Memes

The classic Road Runner vs. Wile E. Coyote scenario reimagined as a programming loop disaster! On the left, Road Runner's code uses a proper while (not edge) { run(); } loop that will terminate when reaching the cliff edge. Meanwhile, poor Coyote is using a do { run(); } while (not edge); loop—checking the condition after execution. He's already run off the cliff because his condition check comes too late! The fundamental difference between pre-test and post-test loops perfectly illustrated through cartoon physics. The variable edge isn't even defined until it's too late, and by then gravity.js has already been imported!