A co-worker in my shop is starting to appreciate the smell of Perl. We had a discussion about recursive function calls in general and he went off writing a small test script to get familiar with the concept.
I told him to use strict and warnings or die. He didn't want to die just yet, so he obeyed. Then he came to me asking for an explanation to something I hadn't foreseen:
#!/usr/bin/perl -w
use strict;
my $line;
open (IN, "<david2");
open (OUT, ">temp");
while ($line = <IN>) {
process($line);
}
exit;
sub process {
my $str=shift;
# my $rest;
($a, $b, $rest) = split(/\s+/,$str,3);
if (defined($a)){
print OUT "$a\t";
}
if (defined($b)){
print OUT "$b\n";
}
if (!defined($rest)){
return (0);
}
process($rest);
}
If he runs the above script, perl will complain that $rest requires explicit package name etc. Fine. Removing the comment before my $rest will make perl happy. Fine again.
The question is: Why doesn't perl require explicit package names for $a and $b?
We have tried the script both under Solaris and Win-32 Active State, Perl 5.6 in both cases. Same result.
Everything will go worng!
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