E-IE0004 — Type mismatch in e-graph conversion

Error Type

Internal Error

Phase

constraint detection during compilation

Python exception

jijmodeling.CompileError

Message

Internal error: type mismatch in the e-graph engine: expected {expected}, got {actual}.

This is a bug in JijModeling - please report it to the developers in community Discord (https://discord.gg/Km5dKF9JjG) with the full error output.

Cause

An internal invariant of the e-graph machinery used for constraint detection was violated; this cannot be produced by normal use of the library. Users may only encounter it during constraint hint detection, which runs by default when compiling a problem.

During extraction from the e-graph, an argument that must be a specific kind of literal (for example, the natural-number axis of a reduction or roll, or a string category label) came back as a different kind of term. Axis arguments are always plain integers at the API boundary, so this mismatch cannot be caused by user code.

Fix

This is a bug in JijModeling. Please report it at the JijModeling community on Discord with the full error output. As a workaround, you can disable constraint hint detection by passing constraint_detection=False to Problem.eval or Compiler.eval_problem.