Function std::env::var

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

Fetches the environment variable key from the current process.

Errors

• Environment variable is not present
• Environment variable is not valid unicode

Panics

This function may panic if key is empty, contains an ASCII equals sign '=' or the NUL character '\0', or when the value contains the NUL character.

Examples

use std::env;

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