You have a (compound) variable that you want to increment and then modulate (ie. bound with modulus some number): 

@a = ( 1 .. 10 );;

$a[$_] = ( $a[$_]+1 ) % 10 for 0 .. 9;;
print @a;;
2 3 4 5 6 7 8 9 0 1

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Instinct wants ++$a[$_] %= 10 for 0 .. 9; to work. It doesn't.

Of course there is $a[$_] = ++$a[$_] % 10 for 0 .. 9;; which works, but is hardly better, especially when $a[$_] might be more like:

$things{ $thing }{$someotherkey}[$someindex]{$somekey}[ $_ ]

[download]
.

A better way?

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In reply to A better (ie.more concise) way to write this? by BrowserUk

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