maybe better readable with a custom function in case of deeply nested HoHoH...

  DB<132> sub cycle { $_[1]++; $_[1] %= $_[0] }

  DB<133> cycle 3 => $h{a}{b}[2]{c};   \%h
 => { a => { b => [undef, undef, { c => 1 }] } }

  DB<134> cycle 3 => $h{a}{b}[2]{c};   \%h
 => { a => { b => [undef, undef, { c => 2 }] } }

  DB<135> cycle 3 => $h{a}{b}[2]{c};   \%h
 => { a => { b => [undef, undef, { c => 0 }] } }

[download]

unfortunately does Perl have no autoboxing, to allow:

$h{a}{b}[2]{c}->cycle(3)

[download]

edit

Ha, it can be emulated with ano-subs! =)

  DB<160> $cycle = sub { $_[0]++; $_[0] %= $_[1] }
 => sub { "???" }

  DB<161> $h{a}{b}[2]{c}->$cycle(3);   \%h
 => { a => { b => [undef, undef, { c => 1 }] } }

  DB<162> $h{a}{b}[2]{c}->$cycle(3);   \%h
 => { a => { b => [undef, undef, { c => 2 }] } }

  DB<163> $h{a}{b}[2]{c}->$cycle(3);   \%h
 => { a => { b => [undef, undef, { c => 0 }] } }

[download]

Cheers Rolf

( addicted to the Perl Programming Language)

In reply to Re^2: A better (ie.more concise) way to write this? by LanX
in thread A better (ie.more concise) way to write this? by BrowserUk

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