[Python-Dev] Interning string subtype instances (original) (raw)

Josiah Carlson jcarlson at uci.edu
Wed Feb 14 20:16:28 CET 2007

Greg Ewing <greg.ewing at canterbury.ac.nz> wrote:

Josiah Carlson wrote: > def intern(st): > ... > > If I remember the implementation of intern correctly, that's more or > less what happens under the covers. That doesn't quite give you everything that real interning does, though. The string comparison method knows when both strings are interned, so it can compare them quickly whether they are equal or not. Your version could detect equal strings quickly, but not unequal strings.

Assuming that dictionaries and the hash algorithm for strings is not hopelessly broken, I believe that one discovers quite quickly when two strings are not equal. Simple testing seems to confirm this, but I didn't work too hard to disprove it either.

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