[Colloq] Masters Thesis Defense - Claire Alvis - Getting Rid of Undefined - December 1st, 2pm, 366 WVH

[Biron, Jessica]

Claire Alvis
2pm December 1st 366 WVH

Getting Rid of Undefined

Dynamically typed languages have suffered from the "undefined" value problem for decades. These languages initialize potentially recursive bindings with an "undefined" value, evaluate the right-hand sides of the definitions, and then assign the results to the variables. As a result, "undefined" may flow into data structures and far-away places, only to cause havoc there.

One solution is to insert checks around all variable references to ensure that they are not "undefined." This paper presents a simple static analysis that can remove almost all of these checks, thus reducing the cost of this solution. It also includes a soundness proof, an empirical evaluation, and an explanation of how this novel analysis is the reaction to a failure to reproduce an early research result on this problem.