Hrm. Note where I declare vars:

package apackage;
my $test="my_variable_name";
my $default_value="the value I set";
$$test = $default_value;
print "the value of \$my_variable_name = $my_variable_name\n";

package main;
$my_variable_name = "A new value";
our $test;
print "the value of \$my_variable_name = $my_variable_name\n";
print "the value of the package variable = $apackage::my_variable_name
+\n";
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Yields:

the value of $my_variable_name = the value I set
the value of $my_variable_name = A new value
the value of the package variable = the value I set
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$/  =  q#(\w)#  ;  sub  sig { print scalar reverse  join  ' ',  @_  } 
+ sig
map { s$\$/\$/$\$2\$1$g && $_ } split( ' ', ",erckha rlPe erthnoa stJu
+" );
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