in reply to Re: Printing last element of hash (unintentionally)
in thread Printing last element of hash (unintentionally)

#!/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]

Replies are listed 'Best First'.
Re: Re: Re: Printing last element of hash (unintentionally)
by Joost (Canon) on Jan 03, 2004 at 21:31 UTC
    $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]
        A /g modifier on a replace (s///) operator replaces all matches (and thus removes all [more] substrings, so there's nothing to match for the following iterations). Leave the /g modifier out, and it will replace the first match (leaving the rest to be replaced by the next match(es)).

        See the section on s/PATTERN/REPLACEMENT/egimosx in perlop: 

         Options are:

                   e   Evaluate the right side as an expression.
                   g   Replace globally, i.e., all occurrences.
                   i   Do case-insensitive pattern matching.
                   m   Treat string as multiple lines.
                   o   Compile pattern only once.
                   s   Treat string as single line.
                   x   Use extended regular expressions.

        [download]

        Joost.

        "What should it profit a man, if he should win a flame war, yet lose his cool?"
[reply]
[d/l]
[select]

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