Trying again.

The Camel book has the following for-loop for enumerating all the variables in a package:

package Test;
$testing = 'TEST';
@test_array = (qw/OneTest TwoTest/);
%test_hash = ('testkey' => 'testvalue');

foreach $symname (sort keys %Test::) {
    local *sym = $Test::{$symname};
    print "\$$symname is defined\n" if defined $sym;
    print "\@$symname is nonnull\n" if         @sym;
    print "\%$symname is nonnull\n" if         %sym;
}
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Slightly altering the loop content, will undef all the package variables.

package Test;
$testing = 'TEST';
@test_array = (qw/OneTest TwoTest/);
%test_hash = ('testkey' => 'testvalue');

foreach my $symname (sort keys %Test::) {
    local *sym = $Test::{$symname};
    if (defined $sym) {$sym = undef; print "\$$symname is cleared\n" }
+;
    if         (@sym) {@sym = undef; print "\@$symname is cleared\n" }
+;
    if         (%sym) {%sym = undef; print "\%$symname is cleared\n" }
+;
}
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It is not a full solution: it will not work under strict (note: lexical variables are not part of any package) and will be dangerous if used in the main package as it will undef also all the special variables