Doh, you're right. But 
$ perl -le 'print ord("5") << 4'
848

[download]
Though I'm not sure we can just say my $swapped = (ord($_) << 4 | ord($_) >> 4) & 0xFF; to fix it. (Don't seem to be able to wrap my head around it right now.)

Makeshifts last the longest.

In reply to Re^3: Nibble swap by Aristotle
in thread Nibble swap by Anonymous Monk

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