Re: Adding many elements to a list

[David Kastrup]

pjb@anevia.com (Pascal J. Bourguignon) writes:

> David Kastrup <dak@gnu.org> writes:
>
>> pjb@anevia.com (Pascal J. Bourguignon) writes:
>>
>>> David Kastrup <dak@gnu.org> writes:
>>>
>>>> pjb@informatimago.com (Pascal J. Bourguignon) writes:
>>>>
>>>>> So better use (require 'cl) (push new-item list)
>>>>>    or (cons new-item list)
>>>>>    or (append (list new-items...) list)
>>>>
>>>> (require 'cl) is quite unnecessary for all of the mentioned
>>>> alternatives.
>>>
>>> Not on emacs version < 23.
>>
>> Nonsense.  push&pop were officially announced in Emacs 21.1.  I may be
>> mistaken, but I think they have been there even earlier.
>>
>> And the other options certainly were there from the earliest versions of
>> GNU Emacs.
>
> C-h f push RET
> push is a Lisp macro in `cl.el'.
> (push x place)
>
> Insert x at the head of the list stored in place.
> Analogous to (setf place (cons x place)), though more careful about
> evaluating each argument only once and in the right order.  place may
> be a symbol, or any generalized variable allowed by `setf'.
>
> [back]
>
> M-x emacs-version RET
> GNU Emacs 22.2.1 (x86_64-unknown-linux-gnu, X toolkit) of 2008-08-21 on simias

Try emacs -Q.  Just because you choose to load some library overloading
the default operators does not mean that other people should do the same
when Emacs will provide those operators by default, with better
performance.

-- 
David Kastrup