What is a macro for concatenating an arbitrary number of components to build a path in Rust?

Question

In Python, a function called os.path.join() allows concatenating multiple strings into one path using the path separator of the operating system. In Rust, there is only a function join() that appends a string or a path to an existing path. This problem can't be solved with a normal function as a normal function needs to have a fixed number of arguments.

I'm looking for a macro that takes an arbitrary number of strings and paths and returns the joined path.

Answer 1

There's a reasonably simple example in the documentation for PathBuf:

use std::path::PathBuf;
let path: PathBuf = [r"C:\", "windows", "system32.dll"].iter().collect();

Answer 2

A normal function which takes an iterable (e.g. a slice) can solve the problem in many contexts:

use std::path::{Path, PathBuf};

fn join_all<P, Ps>(parts: Ps) -> PathBuf
where
    Ps: IntoIterator<Item = P>,
    P: AsRef<Path>,
{
    parts.into_iter().fold(PathBuf::new(), |mut acc, p| {
        acc.push(p);
        acc
    })
}

fn main() {
    let parts = vec!["/usr", "bin", "man"];
    println!("{:?}", join_all(&parts));
    println!("{:?}", join_all(&["/etc", "passwd"]));
}

Playground