Handbook of logic in computer science (vol. 2)
Normal proofs and their grammar
Information and Computation - special issue: symposium on theoretical aspects of computer software TACS '94
Basic simple type theory
Infiniteness of proof (&agr;) is polynomial-space complete
Theoretical Computer Science
Proof finding algorithms for implicational logics
Theoretical Computer Science - Special issue on proof-search in type-theoretic languages
Counting a Type's (Principal) Inhabitants
Fundamenta Informaticae - Typed Lambda Calculi and Applications (TLCA'99)
Hi-index | 0.02 |
In [10] it was shown that it is possible to describe the set of normal inhabitants of a given type Τ, in the standard simple type system, using an infinitary extension of the concept of context-free grammar, which allows for an infinite number of non-terminal symbols as well as production rules. The set of normal inhabitants of Τ corresponds then to the set of terms generated by this, possibly infinitary, grammar plus all terms obtained from those by η-reduction. In this paper we show that the set of normal inhabitants of a type Τ can in fact be described using a standard (finite) context-free grammar, and more interestingly that normal inhabitants of types with the same structure are described by identical context-free grammars, up to renaming of symbols.