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Re: Use of uninitialized value in concatenation (.) or string Error
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| Sukhbir Dhillon 2004-04-04, 9:31 pm |
| Hi! I'm trying to split the string from some file with | (pipe) seperated.
heres one of the string lines from data file.
Sukhbir Dhillon|sdhillon@bridgeport.edu|data.txt|Thank you|student|
I'm using following code to read and split
open (READ_DB, "$dbfile");
while (<READ_DB> )
{
$_ =~ tr/A-Z/a-z/;
($name, $value, $filename, $message, $position) = split(/\|/);
close(READ_DB);
and I found that $position is getting undef value and which gives lots of error mentioned in the subject.
I'm pretty new in perl so please excuse my ignorance.
Thank you
Sukhbir
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| Gunnar Hjalmarsson 2004-04-04, 10:32 pm |
| [ Reply not sent to the defunct group comp.lang.perl. ]
Sukhbir Dhillon wrote:
> Hi! I'm trying to split the string from some file with | (pipe)
> seperated. heres one of the string lines from data file.
>
> Sukhbir Dhillon|sdhillon@bridgeport.edu|data.txt|Thank you|student|
> I'm using following code to read and split
> open (READ_DB, "$dbfile");
> while (<READ_DB> )
> {
> $_ =~ tr/A-Z/a-z/;
> ($name, $value, $filename, $message, $position) = split(/\|/);
> close(READ_DB);
>
> and I found that $position is getting undef value and which gives
> lots of error mentioned in the subject.
Besides the fact that the above code does not compile, I don't see why
it would result in that *warning*.
Please write a *short* but *complete* program that illustrates your
point, and *copy* (don't retype) it into a new message.
--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl
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| Joe Smith 2004-04-04, 11:30 pm |
| Sukhbir Dhillon wrote:
> Sukhbir Dhillon|sdhillon@bridgeport.edu|data.txt|Thank you|student|
> I'm using following code to read and split
> open (READ_DB, "$dbfile");
> while (<READ_DB> )
> {
> $_ =~ tr/A-Z/a-z/;
> ($name, $value, $filename, $message, $position) = split(/\|/);
> close(READ_DB);
>
> and I found that $position is getting undef value
Of course it is. Your program should expect that, and do something like
$message = "" unless defined $message;
$position = "" unless defined $position;
-Joe
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| Sukhbir Dhillon 2004-04-05, 12:31 am |
| On Mon, 05 Apr 2004 03:35:23 +0200, Gunnar Hjalmarsson wrote:
> [ Reply not sent to the defunct group comp.lang.perl. ]
>
> Sukhbir Dhillon wrote:
>
> Besides the fact that the above code does not compile, I don't see why
> it would result in that *warning*.
>
> Please write a *short* but *complete* program that illustrates your
> point, and *copy* (don't retype) it into a new message.
I'm attaching the data file and my module.
data.txt
Sukhbir Dhillon|sdhillon@somemail.com|data.txt|Thank you|manager|
sony Dhillon|sdhillon@bridgeport.edu|data.txt|Thank you|engineer|
perl module.
#!/usr/bin/perl -w
$dbfile="data.txt";
#system "clear";
open (READ_DB, "$dbfile");
while (<READ_DB> )
{
$_ =~ tr/A-Z/a-z/;
($name) = split(/\|/, $_);
print "$name\n";
}
close(READ_DB);
print "\n\nwhich name you want to look up in database : ";
$findname=<STDIN>;
chomp($findname);
open (READ_DB, "$dbfile");
$found = 'false';
while (<READ_DB> )
{
#chomp;
$_ =~ tr/A-Z/a-z/;
($name, $value, $filename, $message, $position) = split(/\|/);
($first,$last) = split(/ /, $name);
if (($name eq $findname)||($first eq $findname)||($last eq $findname)){
print "\nFirstname = $first\n"."Lastname = $last\n";
print "Email = $value\n"."Filename = $filename\n";
print "Message = $message\n";
print "Position = $positon\n";
$found = $findname;
}
}
if ($found ne $findname) {
print "$findname not found in Database\n"; }
close(READ_DB);
###### EOF perl file
Thanks
Sukhbir Dhillon
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| user@domain.invalid 2004-04-05, 12:31 am |
| Gunnar Hjalmarsson wrote:
> [ Reply not sent to the defunct group comp.lang.perl. ]
>
> Sukhbir Dhillon wrote:
>
>
>
> Besides the fact that the above code does not compile, I don't see why
> it would result in that *warning*.
>
> Please write a *short* but *complete* program that illustrates your
> point, and *copy* (don't retype) it into a new message.
>
I'm attaching my program module and sample data file.
Thanks
| |
| Gunnar Hjalmarsson 2004-04-05, 12:31 am |
| Sukhbir Dhillon wrote:
> Gunnar Hjalmarsson wrote:
>
> I'm attaching the data file and my module.
Okay. It's not a module, it's a program.
I can tell you that the failure is caused by a typo, which my version
of Perl lets me know about via warning messages.
Whether your Perl version displays those messages or not, I suggest
that you rewrite your program so that you add
use strict;
as the second line, and declare all the variables using my(). That way
you will
1) learn something that you should always practice when writing
Perl programs, and
2) find the typo. :)
Good luck!
--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl
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