in reply to "2nd param of split in a string.." compilation warning

The second parameter of split is a string,not an array

Perl doesn't produce this message

$ perl -Mstrict -Mwarnings -le " print for split /,/, @ARGV " ro sham +bo 3

or possibly something to do with the fact I'm using Padre.

Probably this. ddging reveals this is Padre "beginner" mode and other Policies