First, make sure you've got warnings enabled everywhere, it'll help you catch typos and other accidents (see also Use strict and warnings):

$ perl -wMstrict -e '$Module::configvar=0; if($Module::confgivar=1)
    { print "<$Module::configvar>\n"; }'
Found = in conditional, should be == at -e line 1.
Name "Module::confgivar" used only once: possible typo at -e line 1.
<0>

[download]

If that doesn't help, you can trace when the variable gets set, put the following debug code at the top of your program, above use Module; and anything else that may make use of $Module::configvar. It will show you exactly when values are stored in the variable.

BEGIN {
    package LoggingScalar;
    require Tie::Scalar;
    our @ISA = 'Tie::StdScalar';
    use Carp 'cluck';
    sub STORE { cluck "STORE"; shift->SUPER::STORE(@_) }
    tie $Module::configvar, 'LoggingScalar';
}

[download]

In reply to Re: package variable does not persist by haukex
in thread package variable does not persist by Anonymous Monk

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.