Numbers can repeat more often than rand's period, but you're right, it won't happen often.
I haven't check the actual source code, but I'm fairly confident that if your perl is using drand48, you won't get repeats any sooner than the period of the RNG (2**48).

In reply to Re^5: Randomising the order of an array by Anonymous Monk
in thread Randomising the order of an array by g0n

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