Dear Perl Monks,

My question is about the scope of package variables. When I run the code listed at the bottom of this post, the following is displayed:

Use of uninitialized value $sv_a in concatenation (.) or string at ./s
+cope_t.pl line 15.
DumpValue: sv_a ...

[download]
I'm a little confused about this, because my understanding of package variables is that they are in scope within subsequent subroutine or method definitions. Why is perl interpreting $sv_a as having an uninitialized value, when it clearly is initialized inside the package?

I'm using perl 5.10.1. If anyone could advise where I'm going wrong, that would be much appreciated. Now for the code ...

#!/usr/local/bin/perl
use 5.010;
use strict;
use warnings;

MainFunction: {
   my $t_obj = ScopeTest->new();
   $t_obj->dump_sv();
}

package ScopeTest;
 my $sv_a = "scalar variable A";

 sub dump_sv {
   print("DumpValue: sv_a ... $sv_a\n");
 }

 sub new {
   my $obj_hv = {};
   bless($obj_hv, $_[0]);
 }
1;

[download]

Cheers, Ron.

In reply to Scope of package variables by rongrw

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