Created
March 24, 2012 02:57
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wat.
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| Python 2.6.7 (r267:88850, Dec 2 2011, 20:27:26) | |
| [GCC 4.4.3] on linux2 | |
| Type "help", "copyright", "credits" or "license" for more information. | |
| >>> a = -1 | |
| >>> b = -2 | |
| >>> hash(a) == hash(b) | |
| True | |
| >>> hash(a) | |
| -2 | |
| >>> hash(b) | |
| -2 | |
| >>> c = -3 | |
| >>> hash(c) | |
| -3 | |
| >>> hash(b) == hash(c) | |
| False | |
| >>> |
Yeah, I know why it happens, it's just amusing that they chose to have -1 hash to -2 (along with -2 hashing to -2).
https://github.com/python-git/python/blob/master/Objects/stringobject.c#L1220
-1 is used as the "not yet computed" cached value, so they (unwisely?) coerce any -1 hash to -2 to allow caching ^_^
Cool, @lunixbochs ! Thanks for tracking that down. :)
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It's a hash function...