Zephyr ASDL

Zephyr ASDL

Paradigm(s)	declarative
Designed by	Appel et al
Appeared in	1997
Computational class	context-free
Reference implementation	Defunct
File extension(s)	.asdl

Abstract Syntax Description Language, more commonly known as Zephyr ASDL to disambiguate it from other syntax description languages, is a wikipedia:domain-specific language introduced in 1997 by researchers at Princeton University and the University of Wisconsin at Madison as part of the Zephyr compiler infrastructure project. It is used by several language implementations, notably the reference implementation of Python, to describe abstract syntax trees (ASTs).

Notable Usage

Despite relative obscurity even within the compiler-engineering ecosystem, Zephyr ASDL is routinely chosen to represent ASTs. The following projects use Zephyr ASDL:

• CPython, the reference implementation of Python [1]
• Typhon, the reference implementation of Monte [2]
• The Oils shell environment [3]

Monte and Oils both support compiling `.asdl` files directly as modules.

Sources

• The Zephyr Abstract Syntax Description Language, Appel, Korn, Serra, & Wang 1997. [4]
• Zephyr ASDL (Abstract Syntax Description Language), math4tots et al 2012. [5]