01/04/2014,Friday,Joe
02/11/2011,Monday,Mary
05/09/2016,Monday,Ann
07/02/2013,MOnday,Marc
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Maybe you have trailing blank lines .

while (my $line = <$lines>) {
  next unless $line =~ /\S/;  # <- add
  chomp $line;
  .
  .
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What does your program look like?

---

Give a man a fish:  <%-{-{-{-<

Here, and I can not get it to work:


#!/usr/bin/perl

use strict;
use warnings;

use Data::Dump 'pp';
use Data::Dumper;

my $file_name = "file.csv";

open my $lines, '<', $file_name
  or die "Can't open file $file_name, $!";

my @parms = qw( date day name );

while (my $line = <$lines>) {

    next unless $line =~ /\S/;  # <- add

   chomp $line;
   
   my $data;

   
   ( $data->{ date }, $data->{ day }, $data->{ name } ) = split(/,/, $
+line);
   
   pp @{ $data }{ (@parms) };
}
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