Try this.

  • It uses a prototype to save you from explicitly taking a reference when you call the sub.
  • It assigns the reference to a localised glob to avoid the need for explicit dereferencing inside the sub.
  • It uses our to satisfy strict.

    Result: Efficient pass-by-reference without the pain of dereferencing. 

    #! perl -slw
use strict;

sub modify (\$) {
    our $data;
    local *data = $_[ 0 ];

    $data =~ s[this][that]g;
    return;
}

my $string = 'this & that;' x 10000;

modify $string;

print substr $string, 0, 24;

    [download]
    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
    "Science is about questioning the status quo. Questioning authority".
    The "good enough" maybe good enough for the now, and perfection maybe unobtainable, but that should not preclude us from striving for perfection, when time, circumstance or desire allow.

    In reply to Re: Simple Pass By Reference by BrowserUk
    in thread Simple Pass By Reference by tomazos

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