Re: Advantage using mapc over dolist

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On Wednesday, December 4th, 2024 at 11:29 AM, Stefan Monnier <monnier@iro.umontreal.ca> wrote:

> > > Richard was strongly opposed to the use of the CL package because of its
> > > "stepping" all over the ELisp namespace. For years, this manifested
> > > itself in the fact that use of CL within Emacs's own code was generally
> > > shunned and tolerated only with (eval-when-compile (require 'cl)),
> > > meaning that you could use CL only when it could be compiled away during
> > > byte-compilation (by macro-expansion and/or inlining). So you could use
> > > `ecase` but not `some`.
> > > How did you decide what should be renamed to cl-*?
> 
> 
> Everything that was defined in the CL library.
> 
> > Why was IF not renamed to cl-if?
> 
> 
> Because `if` was never defined in the CL library but in
> `eval.c` (and the byte-compiler).
> 
> > Why do you think CASE is CL?
> 
> 
> Because it's defined in `cl-macs.el`, i.e. in the CL library (tho this
> file now belongs to the CL-Lib library).
> 
> The renaming was motivated by very practical constraints, so there was
> very little opinion involved in which things were renamed and which weren't.
> 
> "Very little" is not the same as "no opinion", admittedly. For example,
> I did refrain from renaming `setf` and instead re-implemented it outside
> of CL-Lib, integrating it into "core ELisp".
> 
> Also, we later re-re-named things like `cl-caadr` to just `caadr`
> (i.e. integrating it into "core Elisp").
> 
> > How do you feel about code like this?
> > 
> > (defun tempo-is-user-element (element)
> > "Try all the user-defined element handlers in `tempo-user-elements'."
> > ;; Sigh... I need (some list)
> > (catch 'found
> > (mapc (lambda (handler)
> > (let ((result (funcall handler element)))
> > (if result (throw 'found result))))
> > tempo-user-elements)
> > (throw 'found nil)))
> > 
> > Do you think duplicating SOME this way is better than embracing SOME?
> 
> 
> Personally, I think it should (require 'cl-lib) and then use `cl-some`.

That was the code I wrote.  What are you talking about?  How does a simple
question end up like this, with the OP completely disregarded so you can all
argue between yourselves!
 
> > In my code I just require cl-lib and add the cl- prefix where needed and
> > live with that.
> 
> 
> Same here.
> 
> 
> Stefan