Method var

atomic-cli/src/commands/update.rs:135–137

(&self, key: &str)

pub struct StdEnv;
impl EnvLookup for StdEnv {
    fn var(&self, key: &str) -> Option<String> {
        std::env::var(key).ok()
    }
}

/// Shape of `~/.local/state/atomic/install.json` as written by install.sh.