Technical Reports (CIS)
Title
Termination Casts: A Flexible Approach to Termination With General Recursion (Technical Appendix)
Document Type
Technical Report
Date of this Version
1-1-2010
Abstract
This paper proposes a type-and-effect system called Teq↓, which distinguishes terminating terms and total functions from possibly diverging terms and partial functions, for a lambda calculus with general recursion and equality types. The central idea is to include a primitive type-form "Terminates t", expressing that term t is terminating; and then allow terms t to be coerced from possibly diverging to total, using a proof of Terminates t. We call such coercions termination casts, and show how to implement terminating recursion using them. For the meta-theory of the system, we describe a translation from Teq↓ to a logical theory of termination for general recursive, simply typed functions. Every typing judgment of Teq↓ is translated to a theorem expressing the appropriate termination property of the computational part of the Teq↓ term.
Recommended Citation
Aaron Stump, Vilhelm Sjoberg, and Stephanie Weirich, "Termination Casts: A Flexible Approach to Termination With General Recursion (Technical Appendix)", . January 2010.
Date Posted: 19 May 2010
Comments
University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-10-21.