in reply to Re: globally seen variable
in thread globally seen vairable

In this example from perldoc will not $bar declared "our" in Foo conflict in package Bar with "use strict" ? 
package Foo;
our $bar; # declares $Foo::bar for rest of lexical scope
$bar = 20;
..........................
#
package Bar;
use strict;
print $bar; # prints 20, as it refers to $Foo::bar

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Re^3: globally seen variable
by moritz (Cardinal) on Sep 28, 2010 at 18:20 UTC
    Why should it?

    our $bar creates an entry in the current package, and a lexical alias to it. The lexical alias persists to the next package too, because packages and lexical scopes are completely orthogonal.

    Perl 6 - links to (nearly) everything that is Perl 6.
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[d/l]
      I declared 
      our $ERROR_FILE            = $cgi_dir."files/logs/errors.txt";

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      in main program and tried to use it in package: 
      use strict;

package RecordError;

sub RecordError
{
my $error = shift;

## $ERROR_FILE is global var ##

open OF, ">>$ERROR_FILE" or die "cannot open ERROR_FILE $ERROR_FILE\n"
+;
print OF "$error\n";
close OF;
}
1;

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      and it returns 
      Global symbol "$ERROR_FILE" requires explicit package name at E:/.....
+./lib/RecordError.pm line 12.

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      What do I do wrong?
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[d/l]
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        Contrary to the example you gave previously, you now seem to have the two snippets in question in different files. Which means that they don't share a lexical scope. So my explanation with lexical aliases doesn't apply in the new case.

        A lesson you can learn from is that it's not efficient to ask very general questions first, if you really want to solve a specific problem; neither is asking a question that doesn't actually demonstrate the problem.

        To answer your question, you need to either declare a lexical alias in each scope, to the same variable in the same package, or you need to qualify the namespace in one of the locations: 

        {
    our $ERRORFILE = 'foo';
}
{
    package RecordError;
    print $main::ERRORFILE, "\n";

}

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        Perl 6 - links to (nearly) everything that is Perl 6.
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[d/l]

        You need to use our $ERROR_FILE; in each scope in which you need visibility.

        Rather than this comment.... 

        ## $ERROR_FILE is global var ##
open OF, ">>$ERROR_FILE" or die "cannot open ERROR_FILE $ERROR_FILE\n"
+;

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        This serves the same purpose, and gives you that visibility. 

        our $ERROR_FILE;
open OF, ">>$ERROR_FILE" or die "cannot open ERROR_FILE $ERROR_FILE\n"
+;

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        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority".
        In the absence of evidence, opinion is indistinguishable from prejudice.
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In Section Seekers of Perl Wisdom