Undef values from file open

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks!

I cant get it why I am open a txt file and getting undef when I try to print this value: pp @{ $rec }{ (@parms) };

#!/usr/bin/perl

use strict;
use warnings;

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

my $file_name = "file.txt";

open ( LINES, $file_name) or eval {
  warn "Can't open file $file_name.";
 exit;
};

my @parms = qw( date day name );

 while (my $line = <LINES>) {

   chomp $line;

   my $data;
   
   ( $data->{ date }, $data->{ day }, $data->{ name } ) = split(/,/,$l
+ine);

   print "\n $data->{ date }, $data->{ day }, $data->{ name }\n";

   pp @{ $rec }{ (@parms) };

}
[download]

Any suggestion? Thank you!

Comment on Undef values from file open Download Code

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Re: Undef values from file open by Mr. Muskrat (Canon) on Mar 22, 2016 at 20:56 UTC
Did you not see the compilation error? Global symbol "$rec" requires explicit package name at ./1158543.pl line 27. Execution of ./1158543.pl aborted due to compilation errors. You never defined $rec. Update: I'd probably rewrite that like this: `#!/usr/bin/perl use strict; use warnings; use Data::Dump 'pp'; use Data::Dumper; my $file_name = "file.txt"; open my $lines, '<', $file_name or die "Can't open file $file_name, $!"; my @parms = qw( date day name ); while (my $line = <$lines>) { chomp $line; my $data; ( $data->{ date }, $data->{ day }, $data->{ name } ) = split(/,/, $ +line); print "\n $data->{ date }, $data->{ day }, $data->{ name }\n"; pp @{ $data }{ (@parms) }; }` [download]	[reply] [d/l]
Re^2: Undef values from file open by Anonymous Monk on Mar 22, 2016 at 20:59 UTC
typo, Im sorry, its this: `pp @{ $data }{ (@parms) };` [download]	[reply] [d/l]
Re^3: Undef values from file open by Mr. Muskrat (Canon) on Mar 22, 2016 at 21:07 UTC
It works for me. `1/1/16, Mon, foo ("1/1/16", "Mon", "foo") 1/2/16, Tue, bar ("1/2/16", "Tue", "bar")` [download] What does your data look like?	[reply] [d/l]
Re^4: Undef values from file open by Anonymous Monk on Mar 22, 2016 at 21:12 UTC
Re^5: Undef values from file open by poj (Abbot) on Mar 22, 2016 at 21:24 UTC
Re^5: Undef values from file open by AnomalousMonk (Archbishop) on Mar 22, 2016 at 21:27 UTC
Some notes below your chosen depth have not been shown here
Re^2: Undef values from file open by Anonymous Monk on Mar 22, 2016 at 21:26 UTC
Its driving me crazy, I even copied your code and its still: `(undef, undef, undef) (undef, undef, undef) (undef, undef, undef) (undef, undef, undef) (undef, undef, undef) (undef, undef, undef) (undef, undef, undef) (undef, undef, undef) (undef, undef, undef) (undef, undef, undef)` [download] Why?? Can't understand it?!!	[reply] [d/l]
Re^3: Undef values from file open by BillKSmith (Monsignor) on Mar 23, 2016 at 03:08 UTC
You probably have a configuration problem. Download (not cut and paste) Mr.Muskrat's code. Download your own data file and rename it to "file.txt". Run the code that you just downloaded. I have duplicated his results this way. Bill	[reply]