I wondered about building a hash for this. What would be the best way? Are you thinking something like this is better: 
my %data_hash = map { /(\w\s+\d)/ => $_ } @data2;

for my $key ( %data_hash ) {
    print "$data_hash{$key}\n" if grep { /^$key/ } @data1;
}

[download]

I also wondered about anchoring that match. In earlier versions, I did anchor it. But, I wasn't sure if it was necessary given the data set. I think I'll add it back as it's probably safer.

Thanks for the advice!

In reply to Re^3: Help understand why this grep does not work by drmrgd
in thread Help understand why this grep does not work by drmrgd

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