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From: Stefan Monnier <monnier@iro.umontreal.ca>
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Subject: Re: obarray confusion
Date: Fri, 29 Oct 2010 15:00:08 -0400
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> (mapatoms (lambda (s) (incf n))) tells me I have 43061 symbols defined.
> (length obarray) tells me the standard obarray has a size of 1511.

> My understanding is that an obarray is essentially a hash table with
> collision chaining.  But this would mean that the linked list of symbols
> in each bucket has an average length of 43061 / 1511 ≈ 28.

That's right.

> Emacs's symbol lookup couldn't possibly be that inefficient, could it?

I think it not only could.


        Stefan