Decidable subclassing-bounded quantification
- Juan Chen
ACM Workshop on Types in Language Design and Implementation (TLDI 05) |
Published by Association for Computing Machinery, Inc.
Bounded quantification allows quantified types to specify subtyping bounds for the type variables they introduce. It has undecidable subtyping and type checking. This paper shows that subclassing-bounded quantification—type variables have subclassing bounds—has decidable type checking. The main difficulty is that, type variables can have either upper bounds or lower bounds, which complicates the minimal type property.
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