Using Structural Recursion for Corecursion

Yves Bertot (1, 2) , Ekaterina Komendantskaya (1)

1 MARELLE - Mathematical, Reasoning and Software
2 LEMME - Software and mathematics

We address the problem of constructing stream values de- fined by recursive equations that do not respect directly the “guarded- ness” condition, and we concentrate in particular on equations where recursive call appear under functions. We use a correspondence between streams and functions over natural numbers to show that some classes of non-guarded definitions can still be modelled through the encoding as structural recursive functions. In practice, this work extends the class of stream values that can be defined in a constructive type theory-based theorem prover with inductive and coinductive types, structural recursion and guarded corecursion.

Domaines: Informatique et théorie des jeux [cs.GT]

Yves Bertot, Ekaterina Komendantskaya. Using Structural Recursion for Corecursion. 2008. ⟨inria-00322331v1⟩