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arXiv · 2606.22734

Lifting E-Graphs: A Function Isn't a Constant

Philip Zucker
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Abstract

Variables are quite subtle and easy to get wrong. An approach is described to support rigid $\alpha$ canonical variables in an e-graph. The lifting e-graph has a baked-in notion of functional lifting combinator. It is implemented by fattening the usual integer identifiers with thinning bitvectors, lift-pulling smart constructors, and a special thinning-aware union find variation. The approach is inspired by slotted e-graphs and Co-de Bruijn syntax.

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Philip Zucker. 2026-06-22. Lifting E-Graphs: A Function Isn't a Constant. https://arxiv.org/abs/2606.22734

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