Oh, Most Monkilicious Monks...

If an empty string is packed with the  'u*' template and then unpacked with the same template, the resulting value is undefined.

Is this behavior specified? Expected? Desired?

(I have never worked with pack and unpack) UU-encoding before, and have found a simple work-around for the 'problem', if such it be, and there is no compelling need to use this encoding in the first place. But now I'm curious...) 

>perl -v

This is perl, v5.8.2 built for MSWin32-x86-multi-thread
...
Binary build 808 provided by ActiveState Corp.
Built Dec  9 2003 10:19:40
...

>perl -wMstrict -le
"my $ue = pack 'u*', '';
 print 'ue undefined' unless defined $ue;
 print qq{:$ue:};
 my $ud = unpack 'u*', $ue;
 print 'ud undefined' unless defined $ud;
 print qq{:$ud:};
"
::
ud undefined
Use of uninitialized value in concatenation (.) or string at ...
::

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In reply to UU-decode unpack of empty string yields undefined value by AnomalousMonk

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