Add bounded integer types and expressions to Lambda #154
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added 18 commits
September 16, 2025 16:58
Instantiate with unit as default for compatibiity
Bitvectors are no longer a special case in LTy but rather an instance of a type restriction/metadata
Test cases for wf generation Fix a few bugs, refactor and improve comments in code Some AI-generated tests for more bound cases
Change List -> Set to avoid duplicates Remove quantifiers from output wf conditions when possible Add guard_msgs for tests Split tests into separate file Fix bug in abstraction case
Better description of overall algorithm Mark definitions private Comments for most functions Other minor code quality improvements
joscoh
changed the title
added 3 commits
October 7, 2025 11:33
Still special case but need this way so that we can have polymorphic non-restricted type applications
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Adds bounded integer type to
LMonoTyand parameterizesLExprTwith this type to produce Lambda expressions with bounded ints. FileDL/Bounded/BExpr.leancontains an algorithm (with explanation) to translate these terms to ordinary Lambda expressions (with bound assumptions added) and to produce well-formedness conditions. The rest of the changes are simply a result of adding another parameter toLMonoTy.This PR allows the definitions of types like
nat = {x : int | 0 <= x}and expressions likeforall (x: nat), x + 1 > 0. This gets translated to the semantically equivalentforall (x: int), 0 <= x -> x + 1 > 0. For more examples which show the variety of features supported (e.g. external operators with bounded types), see the test cases inStrataTest/DL/Bounded/BExprTest.lean.Currently, this omits the necessary changes to the typing and type inference of Lambda; these will need to be made polymorphic in the newly added
ExtraRestrictparameter. Once this piece is complete, the default parameter ofLMonoTywill beEmptyrather thanBoundTyRestrict, resulting in no overall change to Lambda.By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.