#!/usr/bin/perl
use feature(say);
use strict;
use warnings;
use Text::CSV;
use Tree::Trie;

my $file = $ARGV[0] or die "Need to get CSV file on the command line\n";

my $csv = Text::CSV->new ({
    binary => 1,
    auto_diag => 1,
			  });
my($trie) = new Tree::Trie;

open(my $data, '<:encoding(utf8)', $file) or die "Could not open '$file' $!\n";
while (my $fields = $csv->getline( $data )) {
    $trie->add_data(($fields->[0])=>($fields->[1]));

    my(@sent) = $trie->lookup_data($fields->[0]); #<-- only seems to get the right data in array context
    printf "Just added %s\n with sentiment %s\n", $fields->[0], @sent[1];
}
if (not $csv->eof) {
    $csv->error_diag();
}