Atom pollution

Joe Armstrong (AL/EAB) <>
Tue Feb 22 11:33:52 CET 2005


> I've read that atoms are not garbage collected. But suppose I use the 
> following code:
> 
> a(String) -> b(list_to_atom(String)).
> 
> b(hello) -> ...
> b(ciao) -> ...
> b(bonjour) -> ...
> 
> 
> String can be "hello", "ciao" or "bonjour".
> 
> What happens each time a/1 is called? Is a new atom created 
> each time or 
> there is a sort of "atom hash"?

There is an atom hash table - so a new atom is created the first time
you call list-to_atom, thereafter a pointer to the atom is returned.

Note that the atom hash table is finite and is not garbage collected.

Although it is finite it is "pretty big" (TM) so this fact 
might not worry you.

<<aside>>
How big is "pretty big" (Björn? - anybody????)

<</aside>>

/Joe
 


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> --Corrado
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