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Title: How to Evaluate Blame for Gradual Types, Part 2

Equipping an existing programming language with a gradual type system requires two major steps. The first and most visible one in academia is to add a notation for types and a type checking apparatus. The second, highly practical one is to provide a type veneer for the large number of existing untyped libraries; doing so enables typed components to import pieces of functionality and get their uses type-checked, without any changes to the libraries. When programmers create such typed veneers for libraries, they make mistakes that persist and cause trouble. The question is whether the academically investigated run-time checks for gradual type systems assist programmers with debugging such mistakes. This paper provides a first, surprising answer to this question via a rational-programmer investigation: run-time checks alone are typically less helpful than the safety checks of the underlying language. Combining Natural run-time checks with blame, however, provides significantly superior debugging hints.

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Award ID(s):
1763922 2237984 2116372
PAR ID:
10484541
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ACM
Date Published:
Journal Name:
Proceedings of the ACM on Programming Languages
Volume:
7
Issue:
ICFP
ISSN:
2475-1421
Page Range / eLocation ID:
159 to 186
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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