help-gnu-emacs
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [External] : Re: new `pcase-let' syntax


From: Emanuel Berg
Subject: Re: [External] : Re: new `pcase-let' syntax
Date: Sat, 26 Nov 2022 17:01:51 +0100
User-agent: Gnus/5.13 (Gnus v5.13)

Drew Adams wrote:

>>> (pcase-let ((`(,up ,down)
>>>             (if button
>>>                 `(,#'backward-button ,#'forward-button)
>>>               `(,#'previous-line ,#'forward-line)))) ...)
>> 
>> [...] I also get the feeling this is a hack for the sake of
>> a hack. Is it really that much better than the "classical"
>> 
>> (let ((up #'previous-line) (down #'forward-line))
>>   (when button (setq up #'backward-button down #'forward-button))...)
>
> It gives you more opportunities to use your `,', ``', and
> `)' keys?

Okay, so how do you do this the classical way then?

(pcase-let*((`(,sail ,ho) (if t '(1 2) '(3 4)))
            (msg (format "%s is %s" sail ho)) )
  msg)

Also, it's better than `let' and `setq' because if you make
a typo setq creates a global variable, a bug that silently
enters your code.

Obviously if you gonna do typos all day ever day that's gonna
be a problem even with pcase-let LOL

-- 
underground experts united
https://dataswamp.org/~incal




reply via email to

[Prev in Thread] Current Thread [Next in Thread]