Hello Fellow Monks,

I return to coding after several months off and it seems like I have forgotten everything I ever knew. As a warmup project, I wanted to make a simple parser that would take free-form address data and generate V-card formatted data, with the help of user input. This was supposed to be an easy, one off script, that I have now been working on for a few hours.

Here is how it is suppposed to work: Read through a file one line at a time and present its contents at STDOUT. The user then selects an action, either to split the line on commas, thus breaking up a city and state for later categorization, or the user selects what category the item belongs in. After the user selects a category, the array that holds the data (possibly from a previous split) is shifted, and then it goes through the loop again. Seems straight forward enough. (As a side note: yes I really do want to do it this way, because it really is free-form: some addresses are typical, three or four lines, some are all mushed together in one line, comma delimited.)

But, when a file has this as its contents Medina, OH, and Medina is properly categorized as a city, and the shift is done, initially, $la[0] holds "OH", but when it gets to the bottom of the loop, it is mysteriously undef. I don't see how or why, but I suspect that it is my rusty skills causing me to miss something. Please take a look at the code below and let me know what I am missing.

Thanks,
Scott 

#!/usr/bin/perl -w
use strict;

my @la = ();
my %card;
open FILE, $ARGV[0] or die "couldn't open $ARGV[0]: $!\n";
while (1) {
    my $response;

    if ( scalar @la == 0 ) {
        last if eof FILE;
        chomp( $la[0] = <FILE> );
    }

    if ( $la[0] =~ /^\s*(\S.*\S*)\s*$/ ) {
        $la[0] = $1;
        print <<STDOUT;
1 - split line on commas
2 - Last name
3 - First name
4 - Street address
5 - City
6 - State
7 - Home phone
8 - Work phone
9 - cell phone
0 - other (comment) 
$la[0]
STDOUT

        chomp( $response = <STDIN> );

        if ( $response == 2 ) {
            $card{'ln'} = $la[0];
            shift @la;
        }
        if ( $response == 3 ) {
            $card{'fn'} = $la[0];
            shift @la;
        }
        if ( $response == 4 ) {
            $card{'sa'} = $la[0];
            shift @la;
        }
        if ( $response == 5 ) {
            $card{'ci'} = $la[0];
            shift @la;

print "in response == 5: $la[0]\n";  #"OH" like you would expect
        }
        if ( $response == 6 ) {
            $card{'st'} = $la[0];
            shift @la;
        }
        if ( $response == 7 ) {
            $card{'hp'} = $la[0];
            shift @la;
        }
        if ( $response == 8 ) {
            $card{'wp'} = $la[0];
            shift @la;
        }
        if ( $response == 9 ) {
            $card{'cp'} = $la[0];
            shift @la;
        }
        if ( $response == 1 ) {
            @la = split /\,\s*/, $la[0];
        }
        else {
            $card{'co'} = $la[0];
            shift @la;
        }

if ($la[0] eq undef) {
    print "\$la[0] is undef\n"; #now it's undef!
}

    }
    else {    #nothing matched on this line, probably empty
        warn "WARN: $la[0]\n";
        @la = ();
    }
}
close FILE;

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In reply to typo? variable misteriously becoming undef by scain

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