Re: [PATCH] completion: bash: support recursive aliases

From: Felipe Contreras <felipe.contreras@gmail.com>
Date: Nov 10, 2020, 01:10 UTC
Message-ID: <CAMP44s36ThnMondH8w-VDi4vWNL0Cpkx+o1qRkx_giJvyfh0dg@mail.gmail.com>
In-Reply-To: <xmqq4klyb1w2.fsf@gitster.c.googlers.com>

On Mon, Nov 9, 2020 at 4:29 PM Junio C Hamano <gitster@pobox.com> wrote:

Show 7 quoted lines

> >> So the completion should detect such aliases as well.
>
> Two comments.
>
>  - on design, is it possible to make a set of aliases that form a
>    cycle?  do we need to worry about such case?  what does the
>    current implementation do for an "alias" in such a cycle?

Yes. The first try would be stuck in a loop until the user types CTRL+C.

I already sent a second version that fixes that.

Show 6 quoted lines

>  - on implementation, it is done as a recursive call to the same
>    function, but a loop that naturally maps tail recursion would
>    also be a trivial implementation.  is it worth rewriting the
>    recursive calls into a loop?  if we need to solve the circular
>    references (above) by say limiting the length of the cycle, would
>    such a rewrite make sense as a way to help implementation?

Yes, that can be done. I opted for the minimal change so it was easy to understand what the code was trying to do.

The second version works in the way you suggested.

-- 
Felipe Contreras