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arXiv · 1401.7886

Balancing lists: a proof pearl

Guyslain Naves·Arnaud Spiwack
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Abstract

Starting with an algorithm to turn lists into full trees which uses non-obvious invariants and partial functions, we progressively encode the invariants in the types of the data, removing most of the burden of a correctness proof. The invariants are encoded using non-uniform inductive types which parallel numerical representations in a style advertised by Okasaki, and a small amount of dependent types.

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Guyslain Naves, Arnaud Spiwack. 2014-06-13. Balancing lists: a proof pearl. https://arxiv.org/abs/1401.7886

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