If a subroutine exists in my main script, I don't have to pass a variable into it and get a modified value out of it. But, if I put the subroutine in "common.pl" (and "require" it) then it doesn't have access to the variables of the main script it is required into.

Is there some way to make required libraries see the variables of the script that required them? Is there some way to pass variables to a subroutine so that it modifies the original value?

Right now I have to ($x, $y, $z) = subroutine($x, $y, $z). In one sense this seems like good documentation. But, in another sense the subroutine is making its own local copy of the variables when it shouldn't have to.

Is this where I should be looking at objects? Should my required library really be a package that will share in any "our" definitions?

I've written Perl for 5 years and never understood how to do common subroutines without passing obvious global values in and out of them.

Thanks!

In reply to Global vars? by mfuller

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.