#rustc #file #pass #replace #fn #z #foo #loops

app everybody_loops

A Replacement for the -Z unpretty=everybody_loops pass to rustc

2 releases

Uses new Rust 2021

0.1.1 Apr 17, 2022
0.1.0 Apr 17, 2022

#404 in Rust patterns

MIT/Apache

8KB

everybody_loops

A Replacement for the -Z unpretty=everybody_loops pass to rustc.

Usage

Take a file with a lot of functions, you want to get rid of them.

fn main() {
    let x = 1;
    let y = 2;
    let z = x + y;
}
struct Foo;

impl std::fmt::Debug for Foo {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        write!(f, "Foo")
    }
}

impl Foo {
    fn boo(&self) {
        println!("boo");
    }
}

const f: () = {
    fn noop() {
        let x = 8;
    }
}

Just run

everybody_loops file.rs

And now you have a with much simpler code.

fn main() {
    loop {}
}
struct Foo;
impl std::fmt::Debug for Foo {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        loop {}
    }
}
impl Foo {
    fn boo(&self) {
        loop {}
    }
}
const f: () = {
    fn noop() {
        loop {}
    }
};

Installation

cargo install --locked everybody_loops

Limitations

This will not work for functions with impl Trait in the return type, as the compiller needs to ascribe a concreat type.

Prior Art

  • This used to be a compiller feature, but it was removed in #93913
  • This post by Felix S Klock II first inroduced me to this technique.
  • The code is a thin wrapper over syn and prettyplease, both by dtolnay, who diserves far more credit than me for making this happen.

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

~0.5–1MB
~22K SLoC