title: Rust Compile Time Macros 001
tags: rust

This takes the `PATH` variable, as it was when the binary was compiled.
This does **not** fetch the `PATH` variable at runtime. This is why
it can be a `const fn`.
```rust
use std;

const fn mac() -> &'static str {
    let path: &'static str = std::env!("PATH");
    path
}

fn main() {
    println!("{}",mac());
}
```