Re: Non-Repetitive Random Numbers

[AnomalousMonk]

I am by no means an initiate of the Dark Mysteries™ of random numbers (Update: see reply below of BrowserUk), but here's a possibly interesting use of an iterator:

>perl -wMstrict -le
"use List::Util qw(shuffle);
 ;;
 sub Iterator (&) { return $_[0]; }
 ;;
 sub rand_iter {
   my $total = shift;
   ;;
   my $random = [ shuffle 0 .. $total-1 ];
   ;;
   return Iterator {
     my $n = shift;
     return if $n < 0 or $n > @$random;
     return splice @$random, 0, $n;
     }
   }
 ;;
 my $iter = rand_iter(9);
 ;;
 use Data::Dump;
 dd [ $iter->(0) ];
 dd [ $iter->(5) ];
 dd [ $iter->(4) ];
 dd [ $iter->(1) ];
 dd [ $iter->(2) ];
"
[]

[5, 4, 0, 2, 8]

[7, 3, 6, 1]

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