Developer Guide

Developer Guide#

If you are interested in the internals of EQL or wish to extend it:

  1. Architecture Overview: A high-level view of the system’s design, focusing on the separation between builders and execution graphs.

  2. Expression Hierarchy: An exploration of the symbolic structure and the base classes for all EQL operations.

  3. Variable System: A deep dive into how symbolic variables and domains are handled internally.

  4. Execution Engine: Details on the mechanics of query evaluation and result binding.

  5. Graph and Visualization: Tools and techniques for debugging and visualizing query plans and execution graphs.

  6. Inference Explanation Internals: How the InferenceExplanation system is implemented, including the observer pipeline, Symbol inheritance design, weakref lifecycle management, and the lru_cache memory-leak fix.

  7. Verbalization Internals: How the EQL verbalization pipeline works, including the fragment type hierarchy, rule dispatch via MRO-depth sorting, VerbalizationContext state management, source reference linking, and how to extend the system with new rules or output formats.