Re: obarray

[Juanma Barranquero <lekktu@gmail.com>]

On Sun, Dec 15, 2013 at 1:54 AM, Emanuel Berg <embe8573@student.uu.se> wrote:
> Anyone knows what that is?

What is that you don't understand in its description?

>> Symbol table for use by `intern' and `read'.
>> It is a vector whose length ought to be prime for
>> best results.
>> The vector's contents don't make sense if examined
>> from Lisp programs; to find all the symbols in an
>> obarray, use `mapatoms'.

I think it's pretty clear: is a symbol table for (most) symbols. It is
implemented as a vector, of prime length because of the way the
hashing is done, and it does not make sense to examine it from lisp
*as a vector*, because its elements are not symbols, but have a more
complex structure (basically, they implemente some kind of hash
table). So the way to process all elements of that symbol table is to
use mapatoms; looping over the vector won't give the symbols stored in
the table.

    J