Prototyping CLP(FD) Tracers: a Trace Model and an Experimental Validation Environment

Developing and maintaining CLP programs requires visualization and explanation tools. However, existing tools are built in an ad hoc way. Therefore porting tools from one platform to another is very difficult. We have shown in previous work that, from a fine-grained execution trace, a number of interesting views about logic program executions could be generated by trace analysis. In this article, we propose a trace model for constraint solving by narrowing. This trace model is the first one proposed for CLP(FD) and does not pretend to be the ultimate one. We also propose an instrumented meta-interpreter in order to experiment with the model. Furthermore, we show that the proposed trace model contains the necessary information to build known and useful execution views. This work sets the basis for generic execution analysis of CLP(FD) programs.