jashkenas--coffeescript/documentation/js/existence.js

var footprints, solipsism;
if ((typeof mind !== "undefined" && mind !== null) && !(typeof world !== "undefined" && world !== null)) {
  solipsism = true;
}
if (typeof speed === "undefined" || speed === null) {
  speed = 75;
}
footprints = typeof yeti !== "undefined" && yeti !== null ? yeti : "bear";