Paco: A Coq Library for Parameterized Coinduction

Chung-Kil Hur, Georg Neis, Derek Dreyer and Viktor Vafeiadis

Max Planck Institute for Software Systems (MPI-SWS)

Paco is a Coq library implementing parameterized coinduction. Parameterized coinduction is a technique for defining coinductive predicates (i.e., in Prop), using which one can perform coinductive proofs in a more compositional and incremental fashion than with standard Tarski-style constructions.

The Paco library provides a tactic called "pcofix", replacing Coq's primitive cofix and avoiding its syntactic guardedness checking of proof terms. We have found that pcofix yields clear performance and usability benefits, even on simple examples.

• Tutorial
  
  
• Further Examples
  
  
• Library Source
  • Notations
    
  • Main Definitions and Lemmas
    
  • Internal Tactics and User Tactics
    
    
• Publications
  • The Power of Parameterization in Coinductive Proof.
    In Proceedings of the 40th ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages (POPL 2013).
    [paper: pdf] [coq script: zip]