How far do we stretch the meaning of modify? 
use Smart::Comments;

sub foo ($) {
    my $arg = shift;
    state %cache;

    return $cache{$arg} if exists $cache{$arg};

    my $result = ... something costly ...;

    ### Look MA! No hands! Really...
    
    $cache{$arg} = $result;
}

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In reply to Re: How to test caching? by repellent
in thread How to test caching? by JavaFan

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