Trying the first one, which I thought extremely elegant, I ran into some unexpected behaviour.

dr@dns:~$ cat sscce.pl
use strict;
use warnings;
use feature 'say';

my $str = 'a b c d e f ';
my ($key, undef, undef, undef, undef, undef, $val) = split(" ", $str);
say "Val = <$val>";
my ($key2, $val2) = (split(" ", $str))[0,6];
say "Val2 = <$val2>";
dr@dns:~$ perl sscce.pl
Val = <>
Use of uninitialized value $val2 in concatenation (.) or string at ssc
+ce.pl line 9.
Val2 = <>

[download]

Some of the data I am hacking have only six data points, but with a trailing space. In my original version I was getting a zero length string as the last value as shown in the SSCCE above. But using the more elegant version, it becomes undef and I get the warning shown. Actually, I find it more logical to get undef and changing my code would be no problem, but I can't find any indication why split should behave so apparently inconsistently. I have tried using the regex in my OP, but get the same results as in the SSCCE.

As I said in my OP, I have working code. This isn't important, but it is a gap in my knowledge that I'd like to close.

Regards,

John Davies

In reply to Re^2: Avoiding repeated undefs by davies
in thread [Solved] Avoiding repeated undefs by davies

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