We present a new approach to the old problem of adding side effects to purely functional languages. Our idea is to extend the language with "witnesses," which is based o...
According to Strachey, a polymorphic program is parametric if it applies a uniform algorithm independently of the type instantiations at which it is applied. The notion of relatio...
A pseudolattice L is a poset with lattice-type binary operations. Assuming that the pseudolattice permits a modular representation as a family of subsets of a set U with certain c...
We want to prove \automatically" that a program is correct with respect to a set of given properties that is a speci cation. Proofs of speci cations contain logical parts and ...
The categorical notion of monad, used by Moggi to structure denotational descriptions, has proved to be a powerful tool for structuring combinator libraries. Moreover, the monadic...