# Function std::env::var 1.0.0 [−] [src]

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

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

The returned result is `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 `Err` will be returned.

# Examples

    use std::env;

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

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