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in reply to Re^19: Addional "year" matching functionality in word matching script
in thread Addional "year" matching functionality in word matching script

I have been testing some code on a smaller scale and something is confusing me. Why does the  print "$csv2\n"; command at the end of this script print each full line of the csv. $csv2 has been populated with the key data of csv2hash, so I'm confused as to why it would print each line? Is each line considered a key in this instance? 

#!/bin/perl


 my @csv2 = (); # Creates new empty array @csv2

      open CSV2, "<csv2" or die; # Creates the file handle CSV2, input
+s the data from csv2 into CVS2

      @csv2=<CSV2>; # populates @csv2 array with data from file handle
+ CSV2
      close CSV2;

      my %csv2hash = ();  # Creates empty hash csv2hash

      for (@csv2) {            # for data in @csv2 array
      #chomp;

       my ($title) = $_ =~ /^.+?,\s*([^,]+?),/; #/define the data whic
+h is the title
#Indicate that title data will input into csv2hash
        $csv2hash{$_} = $title;

}

foreach my $csv2 (keys %csv2hash) { # iterates over all the keys in %c
+sv2hash, assigning each one to $csv2



    my $value = $csv2hash{$csv2};



print "$csv2\n"; # This prints the data line by line in the csv2

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Re^21: Addional "year" matching functionality in word matching script
by Corion (Patriarch) on Jul 12, 2016 at 16:59 UTC

    The keys of %csv2hash are the lines:

    for (@csv2) {            # for data in @csv2 array
      my ($title) = $_ =~ /^.+?,\s*([^,]+?),/;
      $csv2hash{$_} = $title;
}

    [download]

    Here, $_ (the current line) is used as a key into %csv2hash.

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      What does this bit of the script do?  my @matches   = ( $value=~/\b$word\b/ig ); specifically the  \b  \b/ig bits?
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        See perlre for explanation.

        \b matches "word boundaries", but in a special meaning of "word". /i makes the matching case insensitive, and /g makes it global, i.e. it matches as many times as it can, and returns all the matching substrings.

        ($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

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