Greetings, Monks!

I am a relatively new Perl programmer. One of my variables is becoming undefined, and I do not know why.

I wanted a script to read in a series of csv files with column headers, and create a main hash, $file_data, to store an array of records for each file. Each 'record' is a hash reference. Everything was working yesterday, but I must have done something, because now the main hash becomes empty after the loop that reads the files.

Here is the code:

@rem = 'source http://www.dostips.com
@CD/d"%~dp0"&perl -s "%~nx0" %*&Exit/b&:';

#perl script starts below here

use Warnings;
use Strict;
use File::Basename;

my %file_data;
my @field_headers = ();

open(OUT, ">inbound.txt")    || die("can't open output file: $!");

# read all of the files dropped onto the batch file
while (<>) {

    #grab and save the column headers on the first line
    if($. == 1) {
        @field_headers = @{split_csv_string($_)} ;

    # read the rest of the lines. each 'record' is a hash with the
    # field name as the key. each 'record' is added to the array of
    # records for that file
    } else {
        my %record;
        my $i = 0;

        foreach my $field_val ( @{split_csv_string($_)} ) {
            $record{ $field_headers[$i] } = $field_val;
            $i++;
        }
        # ****** $file_data IS OK HERE!  ******
        push @{ $file_data{ $ARGV } }, \%record;
    }    

    # reset line numbering on each input file
    if (eof) {    # Not eof().
        close(ARGV);
        @field_headers = ();
    }
}

# ****** $file_data IS BLANK HERE!  ******

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In reply to Why Does My Hash Become Undefined? by Anonymous Monk

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