http://www.perlmonks.org?node_id=960611


in reply to Re^18: can't import using exporter
in thread can't import using exporter

Usually a simple alias BEGIN{ *var=\$DEBUG::var}; is what I remember working -- USED it TONS of times.
{
    package DEBUG;
    our $var = 'foo';
}

{
    package main;
    BEGIN { *var = \$DEBUG::var };
    print "Var is $var\n";
}

$ perl debug_begin.pl
Variable "$var" is not imported at debug_begin.pl line 14.
Global symbol "$var" requires explicit package name at debug_begin.pl 
+line 14.
Execution of debug_begin.pl aborted due to compilation errors.
$ perl -v

This is perl, v5.8.9 built for x86_64-linux

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(Hint: our scope in this example and still the mess of compilation time versus run time in your longer example.)

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Re^20: can't import using exporter (third package)
by tye (Sage) on Mar 20, 2012 at 19:12 UTC

    I disagree with your hints. But, more importantly, they miss an important point: 

    #!/usr/bin/perl -w
use strict;

{
    package DEBUG;
    our $var = 'foo';
}

{
    package main;
    BEGIN { package Other; *main::var = \$DEBUG::var };
    #       ^^^^^^^^^^^^^   ^^^^^^
    print "Var is $var\n";
}
__END__
Var is foo

    [download]

    It doesn't actually have to be a third package, just not the destination package. So you could also use, for example: 

        BEGIN { package DEBUG; no strict 'vars'; *main::var = \$var };

    [download]

    - tye        

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Re^20: can't import using exporter
by perl-diddler (Chaplain) on Mar 24, 2012 at 15:26 UTC
    I'm not sure I get your point.

    I'm not sure if you are trying to point at a solution or what?

    Does Exporter not work for variable names in 6.14? It's documented as supporting them in its pod/manpages, but putting the var in @EXPORT as '$var' and then importing it in another package, doesn't work either in 6.14.

    Does it work in your 5.8? 

    package Debug;
{use parent "Exporter";
our $var="foo";
our @EXPORT=qw($foo);
}
package main;
{import Debug;

print $var;
}'
Name "main::var" used only once: possible typo at -e line 10.
Use of uninitialized value $var in print at -e line 10.

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      Does it work in your 5.8?

      As you've written it, of course it doesn't work.

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        I wondered why I got an extra warning in the cut down version...

        but that's what I get for cuttin down.... can't type straight. ;-)

        ok so export var and not it's contents...

        I get warning, but it appears to work.

        Ok... but that's what I have in the larger program. But that's not the error it puts out... 

        > less testme.pl
#!/usr/bin/perl -w
use strict;
package _Debug;{ 
  our $Filename2Fields  = 1;
  our $HaltOnError      = 2;
  our $DEBUG_OPS        = 3;
  our @EXPORT=qw( Debug $DEBUG_OPS $Filename2Fields $Halt_on_Error);
  use parent 'Exporter';
  sub Debug($$) { my ($what,  $str)=@_;
    if ($what & $DEBUG_OPS) { print STDERR $str; } } }

package Transcode_plug;{
  import _Debug; 
  sub get_fieldAR_from_filename($) {
    my $file=$_[0];
    Debug($Filename2Fields,"get_fieldAR_from_filename($file)\n");
  }
}

Transcode_plug::get_fieldAR_from_filename('dummy');
# vim: ts=2 sw=2
Ishtar:/Audio/scripts> testme.pl
Global symbol "$Filename2Fields" requires explicit package name at ./t
+estme.pl line 16.
Execution of ./testme.pl aborted due to compilation errors.

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        But if I turn off strict and turn off warnings, it runs just fine.

        *cough*.

        How is this not a bug in perl 5.14? Crying wolf is bad, we learned that in grade school.

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