One Tool, Many Languages: Language-Parametric Transformation with Incremental Parametric Syntax

TL;DR

This paper introduces incremental parametric syntax, enabling source-to-source transformations across multiple programming languages with minimal reconfiguration, demonstrated through a multi-language refactoring tool and smaller transformations.

Contribution

It presents a novel approach called incremental parametric syntax for building multi-language source transformations, implemented in Haskell's Cubix system.

Findings

Transformations require little effort to adapt to new languages

Generated code remains readable and preserves original structure

Transformations effectively handle language corner-cases

Abstract

We present a new approach for building source-to-source transformations that can run on multiple programming languages, based on a new way of representing programs called incremental parametric syntax. We implement this approach in Haskell in our Cubix system, and construct incremental parametric syntaxes for C, Java, JavaScript, Lua, and Python. We demonstrate a whole-program refactoring tool that runs on all of them, along with three smaller transformations that each run on several. Our evaluation shows that (1) once a transformation is written, little work is required to configure it for a new language (2) transformations built this way output readable code which preserve the structure of the original, according to participants in our human study, and (3) our transformations can still handle language corner-cases, as validated on compiler test suites.