Through a glass, darkly (invited talk)

Abstract

Reflection gives us a mirror into our programs. Using this mirror, we can see our programs’ structures, perhaps their execution, and maybe even reach through the mirror to change what our programs are and what they do. In this talk, I’ll consider what lives on each side of the mirror and what happens when we cross that boundary. I’ll describe how mirrors let us peer into the middle of our programs, what happens when we reflect on concepts rather than objects, and what happens when we hold up a mirror up to itself. I’ll discuss the way reflection works in the Grace language, and present some prospects for extending it in the future.