Author jdemeyer
Recipients eric.smith, jdemeyer, mark.dickinson, rhettinger, sir-sigurd, tim.peters
Date 2018-09-24.10:01:11
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Message-id <1537783271.67.0.956365154283.issue34751@psf.upfronthosting.co.za>
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> stuff like "t += t >> 16" is a many-to-one function, not a permutation

Yes, I am aware of that. However, the number of collisions here is really quite small. It's very unlikely to hit one by accident.

I also chose >> over << for two reasons:

1. It brings the high-order in play: https://bugs.python.org/msg326117

2. It avoids collisions on the low-order bits: when you do t ^= t << 7, then you are not changing the lower 7 bits at all. So applications using hash(x) % 128 will still see all the problems that we are trying to fix.
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Date User Action Args
2018-09-24 10:01:11jdemeyersetrecipients: + jdemeyer, tim.peters, rhettinger, mark.dickinson, eric.smith, sir-sigurd
2018-09-24 10:01:11jdemeyersetmessageid: <1537783271.67.0.956365154283.issue34751@psf.upfronthosting.co.za>
2018-09-24 10:01:11jdemeyerlinkissue34751 messages
2018-09-24 10:01:11jdemeyercreate