Type Inference for Objects with Base Types
نویسندگان
چکیده
We present a type inference algorithm for the underlying language and type system of a logic (AL [2]) of Abadi and Leino. We approach the problem by following the techniques used by Palsberg and his coauthors [7, 9] whereby, using a language-based representation of types, we construct an automaton to recognise a least-shape type derivation. To overcome technical problems caused in part by the weaker subtype relation and base types, we introduce a generalisation of types which we term pretypes. As a pleasant consequence, pretypes give rise to a natural notion of presolution which allow us to give a cleaner characterisation of least-shape type derivation.
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