1 unstable release
Uses old Rust 2015
0.2.6 | Aug 15, 2018 |
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#15 in #concatenation
10KB
184 lines
interpolate_idents
Warning! This crate uses a procedural macro (known today as a compiler plugin) and can only be used with Rust's nightly distribution.
You cannot currently define a struct, enum, function, or field using
concat_idents!
due to the way macros are parsed by the Rust compiler. This
will hopefully change in the future, but interpolate_idents!
sloppily solves
a side effect of the currently lacking macro system today.
#![feature(plugin)]
#![plugin(interpolate_idents)]
macro_rules! make_fn {
($x:ident) => ( interpolate_idents! {
fn [my_ $x _fn]() -> u32 { 1000 }
} )
}
Now make_fn!(favorite);
is equivalent to
fn my_favorite_fn() -> u32 { 1000 }
.
In short, surround multiple space-separated identifiers (or macro identifer
variables) with square brackets to concatenate the identifiers. Check
tests/tests.rs
for another example.
This plugin was quickly hacked together. It is likely not performant and most certainly not readable.
Crate upkeep
I'm not actively developing on nightly, so I haven't been using this plugin too often. I understand that libsyntax
is a fickle beast, so please file an issue or PR if interpolate_idents
fails to compile on the latest nightly!