Function std::env::var [] [src]

pub fn var<K: AsRef<OsStr>>(key: K) -> Result<String, VarError>

Fetches the environment variable key`key` from the current process.

The returned result is Ok(s)`Ok(s)if the environment variable is present and is valid unicode. If the environment variable is not present, or it is not valid unicode, then` if the environment variable is present and is valid unicode. If the environment variable is not present, or it is not valid unicode, then Err`Err` will be returned.

Examples

fn main() { use std::env; let key = "HOME"; match env::var(key) { Ok(val) => println!("{}: {:?}", key, val), Err(e) => println!("couldn't interpret {}: {}", key, e), } }
use std::env;

let key = "HOME";
match env::var(key) {
    Ok(val) => println!("{}: {:?}", key, val),
    Err(e) => println!("couldn't interpret {}: {}", key, e),
}