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

Greetings, I'm really, really stuck. I have a text file database, I want to be able assign a variable to each entry in the database and possibly create a new object for each entry on a new line (I hope this doesn't sound too vague). I know I can do, for example 
open(FILE, $file) or die "Cannot open $file: $!\n";
while(<FILE>) {
chomp;($creg, $cname, $attribs) = split(/,/);
}
close(FILE);

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But how would I go about creating a new object for each entry (a new entry is on a new line), for example, my text file database is in the format: 
UNIQUE ID, NAME, ATTRIBS
UNIQUE ID, NAME, ATTRIBS

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etc. I've been racking my brain to come up with something for days of google'ing, but I've ran out of ideas.. Any help will be lifesaving, litterally! I don't have much time left at all.. :( maybe something like 
foreach $line(@file) {
chomp;($creg, $cname, $attribs) = split(/,/);
$object = $blah->new();
$object->creg($creg);
...
}

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I don't know :( Thank you for your time kind people, Shibby

Replies are listed 'Best First'.
Re: text file database - Objects?
by svsingh (Priest) on May 09, 2003 at 07:02 UTC
    I have a program that does something similar. Basically, I have a list of movies in a text file. I read each line and then parse the information into an anonymous hash. Then I stick a reference to the hash in a list. With the list, I can access every bit of data about every movie.

    Here's a simplified snippet of the read and store code. 

       my @movieList = ();
   my $index = 0;
   open(DATA, $dataFile);
   while (<DATA>) {
      chomp;
      if (/^\s+$/) { next; } # skip blank lines in datafile

      my @data = split("\t");
      my $title = &getString( shift(@data) );
      my $year = &getString( shift(@data) );

      my $movieRec = {
         'index' => $index,
         'title' => $title,
         'year' => $year,
      };
      push(@movieList, $movieRec);
      $index++;
   } # while
   close(DATA);

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    I hope this gives you some ideas.

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[d/l]
      Minor correction: That's not an anonymous hash. Sorry about that.
[reply]
        Hello again,

        Sorry for my delayed reply, I've been very busy.. Thank you for your replies, they gave me ideas and I have solved my problem!
        Pseudo code

            for($i = 0; $i < scalar($#file +1); $i++)  {
    foreach  ($file[$i])     {    # <-- this is what solves it!
            chomp; ($stuff, $more_stuff) = split(/\|/);
            # ...
        }
    }

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        I didn't really need to create a new object for each data entry.. although it would have been a nice experiment, I found an easier way of doing what I wanted.
        Thanks very much for your support, I appreciate it.

        ~Shibby

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[d/l]
Re: text file database - Objects?
by djantzen (Priest) on May 09, 2003 at 03:11 UTC

    I think you're on the right track, although you might try passing those arguments into the constructor rather than setting them after object creation. Also, if you assign $_ to an actual variable, you ought to use the var rather than rely on the implicit arguments to chomp and split: 

    my @objects;
foreach my $line (@file) {
    chomp($line);
    my ($creg, $cname, $attribs) = split(',', $line);
    my $object = Blah->new($creg, $cname, $attribs);
    push(@objects, $object);
}

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    Alternatively you might store the objects in a hash where the unique ID is the key.
    "The dead do not recognize context" -- Kai, Lexx
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[d/l]
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Re: text file database - Objects?
by nite_man (Deacon) on May 09, 2003 at 06:43 UTC
    Use Perl patterns ( this acrticle - Patterns in Perl will be useful for understanding of advantages of this method). For more detailes look through Perl Design Patterns TinyWiki 
          
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SV* sv_bless(SV* sv, HV* stash);
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