Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
8f1c18d9f4
This PR improves pretty printing of level metavariables: they now print with a per-definition index rather than their per-module internal identifiers. Furthermore, `+` is printed uniformly in level expressions with surrounding spaces. **Breaking metaprogramming change:** level pretty printing should use `delabLevel` or `MessageData.ofLevel`; functions such as `format` or `toString` do not have access to the indices, since they are stored in the current metacontext. Absent index information, metavariables print with the raw internal identifier as `?_mvar.nnn`. **Note:** The heartbeat counter also increases quicker due to counting allocations that record level metavariable indices. In some tests we needed to increase `maxHeartbeats` by 20–50% to compensate, without a corresponding slowdown. |
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