# A Syntactic Approach to Type Soundness

@article{Wright1994ASA, title={A Syntactic Approach to Type Soundness}, author={Andrew K. Wright and Matthias Felleisen}, journal={Inf. Comput.}, year={1994}, volume={115}, pages={38-94} }

We present a new approach to proving type soundness for Hindley/Milner-style polymorphic type systems. The keys to our approach are (1) an adaptation of subject reduction theorems from combinatory logic to programming languages, and (2) the use of rewriting techniques for the specification of the language semantics. The approach easily extends from polymorphic functional languages to imperative languages that provide references, exceptions, continuations, and similar features. We illustrate the…

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