/// This example read `USER`, `ALPHA` and `BETA` from your ENV.
/// If they are not set, this will fail.

// OS Environ Values `X` can read by `$X`.
// And it is always String.
let user = $USER;

// or, `${X}`
let user = ${USER};

{{
    user = user,

    // If you need other type value from String,
    // You can cast values with `as`.
    alpha = $ALPHA as Float,

    // Default Value can be set.
    // ${NAME:-DEFAULT}
    beta = ${BETA:-0.3} as Float,
}}