A logical interpretation of Java-style exceptions

This paper presents a novel, type-based exception analysis for EC (an Exception Calculus)—a higher-order, typed programming language with first-class, Java-style exceptions. EC exceptions are predeclared and are subject to a nominal subtyping relation. Every exception has its own type, and generic exception handling is performed by handling a supertype of all applicable exceptions. Typing is based on result contexts, which are are analogous to the multiple-conclusion succedents in Gentzen’s LK. This paper proves the syntactic soundness of EC, and presents a shallow embedding of EC types and judgments in LK. The embedding gives rise to a pleasant interpretation of subtyping as logical consequence.