Here's a clue

E:\new>perl -MConstants -wle"print for keys %Constants::;;print XX+YY"
Name "main::XX" used only once: possible typo at -e line 1.
import
YY
EXPORT
XX
BEGIN
print() on unopened filehandle XX at -e line 1.


E:\new>perl -MUNIVERSAL -MConstants -wle"print for keys %Constants::;;
+print XX+YY"
import
YY
EXPORT
EXPORT_FAIL
EXPORT_OK
XX
BEGIN
1
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Smells like a bug to me.

In my activeperl5.6.1/5.8.0, UNIVERSAL.pm consists of

require Exporter;
*import = \&Exporter::import;
@EXPORT_OK = qw(isa can);
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I don't know when that happened/changed, but perl is supposed to load UNIVERSAL AUTOMAGICALLY, so you shouldn't need to say use UNIVERSAL;

I wanna hear what tye, merlyn and other people in the know have to say.

update: more clues

E:\new>perl -MConstants -wle"print for keys %UNIVERSAL::;;print XX+YY"
Name "main::XX" used only once: possible typo at -e line 1.
import
can
isa
VERSION
print() on unopened filehandle XX at -e line 1.
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In Universally unimportant and overused tye says

(currently, Exporter::import() is called whenever you use a module that doesn't define any import method at all, even it that module doesn't even mention Exporter -- this will probably be "fixed" at some point but with this you can "fix" it now and see if you are using any modules that depend on this "bug").

I think it's fairly obvious that you should avoid using the package variables @EXPORT unless you also push @ISA, 'Exporter'; cause you'll have unexpected results (and what's the point of an @EXPORT if you don't wanna export anything).

MJD says you can't just make shit up and expect the computer to know what you mean, retardo! ** The Third rule of perl club is a statement of fact: pod is sexy.