For nefarious purposes of my own (actually to make non-predictable unique keys for a db table 8-) I'm doing the following to generate random 25-character strings:

my @chars=("A".."Z","a".."z",0..9);
my $key = join("", @chars[ map { rand @chars } ( 1 .. 25 ) ]);

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How likely is this to ever come up with the same 25 char string more than once? Can I realistically treat this as a non-repeating random function?

In reply to How likely is rand() to repeat? by desertrat

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