Re: Uninitialised value in list assignment

Well, it's warning cause there's an undef on the third split :)

  ($x, $ENV{Z1Z1}) = ( '3', '2,1' );  # first time
  ($x, $ENV{Z1Z1}) = ( '2', '1' );  # second time
  ($x, $ENV{Z1Z1}) = ( '1', undef );  # third time
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To avoid it, you can explicitly get and check the split() results:

  my @arr = split /,/, $ENV{'Z' . uc $foo}, 2;
  $x = shift @arr;
  $ENV{'Z' . uc $foo} = scalar @arr ? $arr[0] : '';   # set to empty s
+tring if nothing available
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Re^2: Uninitialised value in list assignment by Tanktalus (Canon) on Jun 26, 2005 at 22:28 UTC
Yes, but I guess what has me confused is why: `perl -we '$x=1;$y=1;($x,$y)=("1",undef)'` doesn't give any warning, while: `perl -we '$x=1;($x,$ENV{y})=("1",undef)'` does. Upon which I think I just found my solution... just use a temp variable for the two, and the warning goes away... although it seems strange that this warning is only for the list case, and that it only comes up when %ENV is being assigned to. If I use %E rather than %ENV, the error doesn't come up, either. Wierd. Update: Duh, it's because I'm assigning undef to an environment variable Sigh. That warning was a bit too wierd for me to figure out. Chalk that one up to experience - I now have some more. Sorry for wasting your time - hopefully you can learn from this public "D'oh!" moment.	[reply] [d/l] [select]
Re^3: Uninitialised value in list assignment by ysth (Canon) on Jun 26, 2005 at 23:23 UTC
Yup; normally assignment doesn't trigger any warnings, but if there's magic attached to the assignee, it may. Here's another example: `$ perl -we'$\|="abc"' Argument "abc" isn't numeric in scalar assignment at -e line 1.` [download]	[reply] [d/l]