in reply to Variant permutation

How's this?

#! perl -slw use strict; my @array = ( [ 'a', 'b', 'c' ], [ 1, 2 ], ['x', 'y', 'z' ], [ 7, 8, 9 ] ); sub p { my( $stem, @a ) = @_; return @{ shift @a } if @a == 1; map { my $pre = $_; map( { $pre . $_ } p( $stem . $_, @a ) ), $pre; } @{ shift @a }; } print for p( '', @array ); __END__ P:\test>287900-2 a1x7 a1x8 a1x9 a1x a1y7 a1y8 a1y9 a1y a1z7 a1z8 a1z9 a1z a1 a2x7 a2x8 a2x9 a2x a2y7 a2y8 a2y9 a2y a2z7 a2z8 a2z9 a2z a2 a b1x7 b1x8 b1x9 b1x b1y7 b1y8 b1y9 b1y b1z7 b1z8 b1z9 b1z b1 b2x7 b2x8 b2x9 b2x b2y7 b2y8 b2y9 b2y b2z7 b2z8 b2z9 b2z b2 b c1x7 c1x8 c1x9 c1x c1y7 c1y8 c1y9 c1y c1z7 c1z8 c1z9 c1z c1 c2x7 c2x8 c2x9 c2x c2y7 c2y8 c2y9 c2y c2z7 c2z8 c2z9 c2z c2 c

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