in reply to Re^5: Addional "year" matching functionality in word matching script
in thread Addional "year" matching functionality in word matching script

I can see this print each line in the title and the  => bit shows the year being extracted (not sure that's the right word) from the title. 
sub find_year {
    my( $str ) = @_;
    my $year;
    $year = $1
        if( $str =~ /\b((?:19|20)\d\d)\b/ );
    return $year
}


for my $title (
    "Let's party like it's 1999",
    "If 6 was 9",
    "If 6 was 9",
    "Summer of 69",
    "Disco 2000",
) {
    print $title , " => ", find_year($title), "\n";
}

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One thing I'm not sure of is, I've tried to integrate the info above so that I can use the $title from a csv file rather than titles typed into the script (as in the above example). I have attempted this below but it's not working. I'd appreciate if someone could tell me what exactly i'm doing wrong. I know I'm being prompted to learn which I'm happy to do, but I think I would learn faster if someone told me what I have done wrong in the piece of code below. 
sub find_year {
    my( $str ) = @_;
    my $year;
    $year = $1
        if( $str =~ /\b((?:19|20)\d\d)\b/ );
    return $year
}

#get the title from csv3

open CSV3, "<csv3" or die;

while (<CSV3>) {

  chomp;

  my ($title) = $_ =~ /^.+?,\s*([^,]+?),/; #/ match the title
}

for my $title {
print $title , " => ", find_year($title), "\n"; }

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Re^7: Addional "year" matching functionality in word matching script
by Corion (Patriarch) on Jun 28, 2016 at 14:17 UTC

    This second loop creates its own $title variable:

    for my $title {
    print $title , " => ", find_year($title), "\n";
}

    [download]

    What you want instead is to integrate that call to find_year into your while loop:

    while( <...>) {
    ...
    my ($title) = ...;

    print "Have title '$title'\n";

    print $title , " => ", find_year($title), "\n";
};

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      Ok, thanks that's working nicely now that I'm printing it within the while loop. Is there any way to maintain the variable outside the while loop?
[reply]

        Sure there is, but you will need to think about what value the variable should have after the while loop ends:

        my $year;
while( my $title = <CSV3> ) {
    $year = find_year( $title );
};
print "I now have a year of '$year'\n";

        [download]

        Do you really want to keep only one year from all the titles stored in your CSV file?

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