• anton
    link
    fedilink
    arrow-up
    1
    ·
    1 year ago

    Such a case would be the single function having a side effect*. This allows the caller to chose when to execute the side effect or to drop the result without executing it.

    In my opinion that is fine with fn_once but not into because of the implicit contract of these traits.

    * = I’m counting expensive computation, but not allocation and memcopy as a side effect in this comment.