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

I have a file with some data which i want to crunch into an AOH.Thed data corresp. to a record needs to be put into a hash.The data is of the form

Record#1:
name:'George Simpson'
age:25
occupation:'PLumber' ... so on

I use the following code to seperate the 'name'(to be the key of hash) & 'George Simpson'(to be the corresp value)

while(defined($index = <$inp_file>))
    {
        if (($index =~ m"Record#") && ((keys %$hash_ref) != 0))
        {
            return ($hash_ref);
        }
        next if ($index =~ m"Record#");
        $index =~ m"(.*?): (.*)";

        my $key = $1;
        my $val = $2;

    #1    $key =~ s"^\s+""g;
    #2    $key =~ s"\s+$""g;
    #3    $val =~ s"^\s+""g;
    #4    $val =~ s"\s+$""g;

        $hash_ref->{$key} = $val;
    }

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Problem is that the four #ed lines above that i use to clean empty spaces is generating a warning which says :

Use of uninitialized value in substitution (s///)at f2ds4.pl at line 30 , <GENO> line 13

I am a bit lost here .. though the script runs and gives results, Id like to know which uninitialized value it is talking about ! thank you -pacman

edit by thelenm: added code tags

Replies are listed 'Best First'.
Re: cleaning up spaces on either side of an extracted string
by cLive ;-) (Prior) on Mar 19, 2004 at 07:48 UTC
    Try changing this: 
    $index =~ m"(.*?): (.*)";

my $key = $1;
my $val = $2;

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    to this: 
    my $key='';
my $value='';
if ($index =~ m"(.*?): (.*)") {
    $key = $1;
    $val = $2;
}

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    Never assume a match will exist. Consider this piece of careless code : )

    'boo!' =~ /(.*)/;

$test_string = "this is a test sentence.";

$test_string =~ /(\w+)$/;

my $last_word=$1;

print "$last_word\n";

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    If you assume a match will take place, you'd get extremely confused :)

    cLive ;-)

[reply]
[d/l]
[select]
      hey clive thanks ..i'll keep that in mind .
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Re: cleaning up spaces on either side of an extracted string
by matija (Priest) on Mar 19, 2004 at 07:43 UTC
    Well, it appears that in some circumstances, either $key, $val or possibly both can be undefined. Since that probably indicates a problem with the syntax of your input file, you should test for it: 
      unless (defined($key) && defined($val)) {
    warn "Problem in input: <$index>\n";
  } else {
    $key =~ s"^\s+""g;
    $key =~ s"\s+$""g;
    $val =~ s"^\s+""g;
    $val =~ s"\s+$""g;
    $hash_ref->{$key} = $val;
  }

    [download]
[reply]
[d/l]
      hey mat thanks for the tip , it worked :D
[reply]

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