filter-list

filter-list

[Michael Heerdegen]

Hi,

Is there something like

| (defun filter-list (pred list)
|   "Make a list of all LIST elements satisfying PRED."
|   (let ((deleted '#:deleted))
|     (delete deleted
|             (mapcar (lambda (el) (if (funcall pred el) el deleted))
|                     list))))

existing in Emacs Lisp?  I can't find it, but I would expect such
an elementary function would be built in.  Do I miss something?


Thanks,

Michael.

Re: filter-list

[Stefan Monnier]

> Is there something like
> | (defun filter-list (pred list)

There's cl-remove-if.


        Stefan

Re: filter-list

[Grant Rettke]

https://github.com/magnars/dash.el#-filter-pred-list
Grant Rettke | AAAS, ACM, FSF, IEEE, Sigma Xi
grettke@acm.org | http://www.wisdomandwonder.com/
“Wisdom begins in wonder.” --Socrates
((λ (x) (x x)) (λ (x) (x x)))
“Life has become immeasurably better since I have been forced to stop
taking it seriously.” --Thompson


On Wed, Apr 16, 2014 at 5:01 PM, Michael Heerdegen
<michael_heerdegen@web.de> wrote:
> Hi,
>
> Is there something like
>
> | (defun filter-list (pred list)
> |   "Make a list of all LIST elements satisfying PRED."
> |   (let ((deleted '#:deleted))
> |     (delete deleted
> |             (mapcar (lambda (el) (if (funcall pred el) el deleted))
> |                     list))))
>
> existing in Emacs Lisp?  I can't find it, but I would expect such
> an elementary function would be built in.  Do I miss something?
>
>
> Thanks,
>
> Michael.
>
>

Re: filter-list

[Michael Heerdegen]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

> > | (defun filter-list (pred list)
>
> There's cl-remove-if.

Indeed, thanks.  I was overlooking it because it's only in a side note
in the cl manual.

Michael.

Re: filter-list

[Michael Heerdegen]

Grant Rettke <gcr@wisdomandwonder.com> writes:

> https://github.com/magnars/dash.el#-filter-pred-list

Indeed a good source for diverse list processing functions.

Thanks,

Michael.