$b++ needs to create a new anonymous scalar because the result is different than the $b.

++$b just returns a pointer to $b. 

$ perl -le'my $b = 4; $r = \( $b++ ); $$r = 20; print $b'
5

$ perl -le'my $b = 4; $r = \( ++$b ); $$r = 20; print $b'
20

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In reply to Re^4: Summing Up Array Elements By Group by ikegami
in thread Summing Up Array Elements By Group by neversaint

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