Macro iif::iif_opt

macro_rules! iif_opt {
    ( $check:expr, $true_case:expr ) => { ... };
}

Returns an option, depending on the evaluation of an expression. Example:

use iif::iif_opt;

let active = true;
let active_text = iif_opt!(active, "Active");

assert_eq!(active_text, Some("Active"));

let active = false;
let active_text = iif_opt!(active, "Active");

assert_eq!(active_text, None);