bug#30039: 26.0.90; [26.1] Making my code warning free is impossible with when-let

[Noam Postavsky]

On Wed, Jan 10, 2018 at 5:57 PM, Eric Abrahamsen
<eric@ericabrahamsen.net> wrote:

> Right, and the issue wasn't the introduction of when-let*, it was the
> very short life-cycle of when-let.

I don't understand how that leads to this:

    I have to choose between compiler warnings on the one hand,
    or multiple users running an Emacs without the function, on the other.

Supposing when-let* was only introduced as a replacement to when-let
in Emacs 30, you would still have to choose between users of Emacs 29
reporting errors, or get deprecation warnings when compiling in Emacs
30. The (hypothetical) longer non-deprecated existence of when-let
over versions 26,27,28,29 wouldn't help (unless you plan to stop
developing your package before Emacs 30, I guess).