in reply to RFC: Kinda pseudo-shuffle using sort
The comparison function is required to behave. If it returns inconsistent results (sometimes saying $x1 is less than $x2 and sometimes saying the opposite, for example) the results are not well-defined.
It doesn't say undefined behaviour, so I guess you're in the clear as far as not crashing is concerned?
That said, the "quality of the randonmess" can change at any time. sort's algorithm has been changed before, and could change again.
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