Abstract
Programming-by-example (PBE) from computation traces is hard to realize because of the difficulty in supporting an interactive environment in which traces can be easily written and edited. In this paper, we propose a new approach to PBE called the computing-as-editing paradigm (CAEP) and describe a PBE system based on this paradigm. The system has a 2D language of constraints for writing computation traces. Constraints represent rules that hold on every computation trace of the same program. In order to uniformly treat rules on traces as constraints, we introduce a new kind of constraint called an iteration constraint, which can represent iteration with fixed increments by simply pointing to the first and second iteration steps. We also develop a new algorithm for inferring conditional expressions in iteration.