#proc-macro #proc-macro2 #spans #compiler #type #syn #source

proc-macro2-impersonated

A substitute implementation of the compiler’s proc_macro API

2 releases

0.1.1 Apr 15, 2020
0.1.0 Apr 14, 2020

#1504 in Procedural macros

48 downloads per month
Used in 2 crates

MIT/Apache

92KB
2.5K SLoC

proc-macro2-impersonated

Adapted from proc-macro2 Removed wrap proc-macro for correct span outside rust sources Not use in proc-macro context if you don't know what you do

Build Status Latest Version Rust Documentation

A wrapper around the procedural macro API of the compiler's proc_macro crate. This library serves two purposes:

  • Bring proc-macro-like functionality to other contexts like build.rs and main.rs. Types from proc_macro are entirely specific to procedural macros and cannot ever exist in code outside of a procedural macro. Meanwhile proc_macro2 types may exist anywhere including non-macro code. By developing foundational libraries like syn and quote against proc_macro2 rather than proc_macro, the procedural macro ecosystem becomes easily applicable to many other use cases and we avoid reimplementing non-macro equivalents of those libraries.

  • Make procedural macros unit testable. As a consequence of being specific to procedural macros, nothing that uses proc_macro can be executed from a unit test. In order for helper libraries or components of a macro to be testable in isolation, they must be implemented using proc_macro2.

Usage

[dependencies]
proc-macro2-impersonated = "1.0"

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Dependencies

~57KB