I don't think that is really the OP's problem. What you suggest can be checked trivially by:

use strict;
use warnings;

my @array = (1 .. 8);

print "Before: @array\n";
nastyModifyParamsSub (@array);
print "After: @array\n";


sub nastyModifyParamsSub {
    for my $element (@_) {
        ++$element;
    }
}

[download]

Prints:

Before: 1 2 3 4 5 6 7 8
After: 2 3 4 5 6 7 8 9

[download]

Which shows that modifying the parameters is possible and that there is nothing magical about requiring $_ to do it. The following though shows one way that OP's code could be going awry:

use strict;
use warnings;

my @array = (1 .. 8);

print "Before: @array\n";
nastyModifyParamsSub (@array);
print "After: @array\n";


sub nastyModifyParamsSub {
    for (@_) {
        ++$_;
        clobberDefVar ();
    }
}


sub clobberDefVar {
    $_ = 0;
}

[download]

Prints:

Before: 1 2 3 4 5 6 7 8
After: 0 0 0 0 0 0 0 0

[download]

The bottom line though to that the OP's description is an fuzzy unclear thing and there is too much code and no data at all.

True laziness is hard work

In reply to Re^3: Modifying a parameter to a recursive function by GrandFather
in thread Modifying a parameter to a recursive function by CoDeReBeL

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.