News: 0000828486

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[$] "Structural pattern matching" for Python, part 2

([Development] Sep 1, 2020 15:50 UTC (Tue) (jake))

Reference: 0000828486
News link: https://lwn.net/Articles/828486
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n = ((n >> 1) & 0x55555555) | ((n << 1) & 0xaaaaaaaa);
n = ((n >> 2) & 0x33333333) | ((n << 2) & 0xcccccccc);
n = ((n >> 4) & 0x0f0f0f0f) | ((n << 4) & 0xf0f0f0f0);
n = ((n >> 8) & 0x00ff00ff) | ((n << 8) & 0xff00ff00);
n = ((n >> 16) & 0x0000ffff) | ((n << 16) & 0xffff0000);

-- C code which reverses the bits in a word.