A Type Checking Algorithm for Higher-rank, Impredicative and Second-order Types

Peng Fu

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arXiv · 1711.04718

A Type Checking Algorithm for Higher-rank, Impredicative and Second-order Types

Peng Fu

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Abstract

We study a type checking algorithm that is able to type check a nontrivial subclass of functional programs that use features such as higher-rank, impredicative and second-order types. The only place the algorithm requires type annotation is before each function declaration. We prove the soundness of the type checking algorithm with respect to System $\mathbf{F}_{\omega}$, i.e. if the program is type checked, then the type checker will produce a well-typed annotated System $\mathbf{F}_{\omega}$ term. We extend the basic algorithm to handle pattern matching and let-bindings. We implement a prototype type checker and test it on a variety of functional programs.

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Peng Fu. 2017-11-13. A Type Checking Algorithm for Higher-rank, Impredicative and Second-order Types. https://arxiv.org/abs/1711.04718

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