With warnings (-w) on, the following code produces a 'use of uninitialised value in join' error:

my @data = (); 
while (@data = $sth->fetchrow_array){
 print TSCH join(' ',@data),"\n";
}
[download]

The above was what I attempted after first using (which produced the same error):

while (my @data = $sth->fetchrow_array){
 print TSCH join(' ',@data),"\n";
}
[download]

perldiag says:

Use of uninitialized value%s 
  (W uninitialized) An undefined value was used as if it were 
  already defined. It was interpreted as a "" or a 0,  but maybe
  it was a mistake. To suppress this warning assign a 
  defined value to your variables.
[download]

The while loop keeps looping until the expression evaluates to false. The fetchrow_array method returns an empty list when there is no more data, and Perl treats that as a false value; and so the loop stops. So I cannot see why join would see @data with an uninitialized value.

I am sure I am overlooking something obvious, but perhaps not. I, a humble acolyte, seek your wisdom.

--
notsoevil
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