ref: 7088e222cf1b0ae17607ce0ac232067a172b851e
parent: 6b45f935bd240eb066fe4edd49b8cd0853bc5dd9
author: Ori Bernstein <ori@eigenstate.org>
date: Tue Oct 7 16:17:58 EDT 2014
Keep track of source files as well as line numbers.
This makes our error messages better *AND* makes it easier to
provide good debug info later.