my @items;

foreach my $key (keys %hash){
   push(@items,$key);
}

[download]

Or simply: 

my @items = keys %hash;

[download]


my $rxMatchItems;
{ local $" = q{|};
   $rxMatchItems = qr{(?:@items)};
}

[download]

Or simply: 

my $rxMatchItems = do { local $" = q{|}; qr{(?:@items)} };

[download]


Because your %hash is empty your pattern match becomes: 

$ perl -le'my @items; my $rxMatchItems = do { local $" = q{|}; qr{(?:@
+items)} }; print $rxMatchItems'
(?-xism:(?:))

[download]

And the pattern (?-xism:(?:)) will match everything.

In reply to Re: Large File Parsing by jwkrahn
in thread Large File Parsing by RobertCraven

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