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Re: Basic questions about elisp


From: Pascal J. Bourguignon
Subject: Re: Basic questions about elisp
Date: Fri, 06 Nov 2009 22:18:03 +0100
User-agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/22.3 (darwin)

Francis Moreau <address@hidden> writes:
>>> When I wrote '(2), I suppose the elisp interpreter to create a new
>>> list.
>>
>> It does so, but at read time.  Not execution time.
>>
>
> Ah ok I see what you mean now.
>
> That's a pretty important point, is this part covered by the elisp info ?

Yes.



> Actually the same stands for the implementation of the list, where
> nconc, length... are O(n). I wouldn't have thought that lists are really
> implemented by the car & cdr thing only.

Why not?  If people have been repeating for 50 years that lisp lists
are implemented with cons, car and cdr...  


(Note however that if you need a different kind of list, you can
always implement your own abstract data type in any way you like.)

-- 
__Pascal Bourguignon__


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