Size in bytes of a dictionary

David Bolen db3l at
Thu Sep 20 01:27:47 CEST 2001

Don O'Donnell <donod at> writes:

> Also beware of automatic interning of strings.  Of course this won't be
> an issue with your key strings, since they must be unique, but duplicate
> value strings may use the same memory location.  I'm not sure under what
> conditions auto-intern takes place but it seems to be related to the
> length of the string.  Here's a little test I just ran:

It's of course potentially version specific, but I think in all recent
(1.5.2+) variants of CPython the interning rule is that it must be a
string consisting soley of alphanumerics and the underscore.  Length
does not appear to be a factor.  (See compile.c in the CPython

-- David
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