in reply to Printing last element of hash (unintentionally)

pretend %data contains something like 12::34::56::78::90::09

I'm closing my eyes and pretening really hard..... No, doesn't work..... You seem to be misinformed about the structure of hashes in Perl. You cannot have a hash containing one element, a hash (in Perl) contains key/value pairs. Please show where you set the data in %data.

Also, this code: 

$specifics =~ s/\[a\]/a/g;
$specifics =~ s/\[b\]/b/g;

[download]
Replaces all occurences of "[a]" and "[b]" with "a" and "b" respectively; don't you mean $specifics =~ s/\[a\]/$a/g; instead?

Also also, $specifics is not being assigned any value in the piece of code you posted.

I think your problem lies in one or more of the following points (I'm using Devel::PSI here, so I might be wrong):

  1. You assing something to %data that does not fit in a hash in one way or the other.
  2. Your use of split(/::/, $data{$_}); suggests you'd be better of using arrayrefs as values.
  3. You are trying to be really clever with user input that doesn't confirm to your expectations.
Please explaing what you are trying to do, and then show how you are trying to accomplish it. Somebody might be able to help you more than I am at this point.

Good luck,
Joost.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

Replies are listed 'Best First'.
Re: Re: Printing last element of hash (unintentionally)
by Anonymous Monk on Jan 03, 2004 at 21:18 UTC 
    #!/usr/bin/perl


my %data;
my $data     = "data.dbm";  

my $lookup    = url_param('lookup');

tie %data, 'SDBM_File', $data, O_CREAT | O_RDWR, 0644;
if ( !tied %data ) {
    print "error $!.\n";
    }

print header();
print start_html();

print <<"ALL";

<table width="470" border="0">
<form name="extract" method="post" action="extract.pl">
<tr><td colspan="2"><textarea name="specifics" cols="40" rows="5" id="
+specifics">$specifics</textarea></td></tr>
<tr><td><input type="submit" name="submit1" value="submit"></td></tr>
</form>
</table>

ALL

if (param('submit1'))
{

 foreach (sort keys %data)
 {
   my ($a, $b, $c, $d, $e, $f) = split(/::/, $data{$_});

$specifics =~ s/\[a\]/$a/g;
$specifics =~ s/\[b\]/$b/g;
$specifics =~ s/\[more\]/$data{$_}/g;
$specifics =~ s/\[c\]/$c/g;
$specifics =~ s/\[d\]/$d/g;
$specifics =~ s/\[e\]/$e/g;
$specifics =~ s/\[f\]/$f/g;



   print "$specifics<br>";

  }

}

    [download]
[reply]
[d/l]
      $specifics =~ s/\[more\]/$data{$_}/g; Replaces all occurences of [more] with the current value of $data{$_}. You are using this code in a loop that iterates over the entries of the hash, but unless the values in %data acutally contain the literal string [more], only the first iteration will match.

      That is probably a problem. :-)

      I'm still not sure what you want to do, and if the hash actually contains what you think it does, though.

      Please also try running your code with: 

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

      [download]
      That will show some other problems in the code you posted above (you probably just posted a snipped of the code, but it suggests more things are going wrong than you are aware of)

      Joost.

      "What should it profit a man, if he should win a flame war, yet lose his cool?"
[reply]
[d/l]
[select]
        That should only change the more for each individual iteration since I'm running through each key in the hash. Each key should print a different $data{$_}.
[reply]

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