yes, it is.

Place following line into your program:

    $DB::single=1;
[download]

and then run with debugger available

perl -d foo.pl
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or even better

perl -d:ptkdb foo.pl
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or even better more

perl -d:tkdb foo.pl
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last mentioned one does not offer same feature set as ptkdb, but very soon will do even much better, as it has large amount of optimizations.

in case of perl -d foo.pl you will need to type 'r' once your program starts to make it run.

update: removed DB::DB(); as it is actually not needed, thanks to wisdom from Eliya