unless isn't a looping construct, it's a branching/control construct, but that's not important, what is important is the scoping of the $errorcount variable (see Coping with scoping as usual). You need to define the variable in the containing scope of the unlesses and the if.

If you declare the variable once within each block you will be accessing a different variable in the block. If you want to access the same variable it must be declared at a containing scope so that it is visible (a containing lexical scope if you're using lexicals, and a containing dynamic scope if you're using package globals, which you shouldn't be for something like this)

--
integral, resident of freenode's #perl

sub print_error {
    my $message = shift;
    print "<br><font color='red'>$message</font>";
    # etc..
}

unless($title and $url and $description and $keywords) {
    $title
        or print_error "Please enter a title.";

    $url
        or print_error "Please enter a valid address.";

    $description
        or print_error "Please enter a description.";

    $keywords
        or print_error "Please enter some keywords.";

    # ...
}
[download]

You could still do a lot better if $title, $url etc where all stored in a hash. See Mark-Jason Dominus' excellent Program Repair Shop and Red Flags article series on Perl.com.

Update: thanks to The Mad Hatter for catching a small mishap. (s/$shift/\$message/)

Makeshifts last the longest.

  my $errorcount = 0;
  unless ($title) {
  ...
[download]

# $errorcount = 1;  # probably not what you want
                    # better:
  $errorcount = $errorcount + 1;   # or
  $errorcount += 1;                # or
  $errorcount++;
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Abigail

"Well, you're wrong."

Laziness, impatience and hubris may go a long way to getting the job done, but I don't think Larry was talking about interpersonal skills. Many people, especially those who are asking for help from those who have more experience, are turned off by this kind of attitude. Saintly may be your technical skills, but walkest thou friendly amongst the throng, I beseech.

--
[ e d @ h a l l e y . c c ]

halley, some people simply don't know how to offer constructive criticism without sounding harsh and don't see the point in doing so. Abigail is one of those and I think will always be so. There's not much point in trying to change the leopard's spots.

Wally Hartshorn

(Plug: Visit JavaJunkies, PerlMonks for Java)

Damn, did you just sign up with AOL today? You actually think saying "Well, you're wrong" when helping someone out online is mean? Abigail-II donates time to help someone out, gives a perfectly good answer in a direct fashion, and you have the nerve to suggest that's impolite? Have you ever seen an online discussion before? This is as good as it gets buddy. I wish more people were this straightforward. I can't stand wasting my time reading the sugar-coated, carefully phrased, drivel that I so often get in response to questions. I just want an answer damn it! Enclose it in <youareafreakingmoron> tags if you need to, I don't care in the slightest and I'll still thank you.

Sheesh, I didn't know there were still any left.

What's your point? That he was right? Or that we should lie? Or that we should be like sales people and sugarcoat everything?

Come on, this isn't kindergarten. If you can't stand the heat, stay out of the kitchen. If you can't face the fact you might be wrong, don't ask questions here.

Grow up.

Abigail

You're right, I seem to have forgotten the basics in years of useing strict; - thanks for the correction.

The logic of the sample is not good for a real CGI but the technique itself works great and I get to show the serial comma function again. :)

#!/usr/bin/perl
#=========================================================
use warnings;
use strict;
use CGI qw(:standard);
#=========================================================
print header(), start_html(), start_form();

my @param_names = qw( title address description );

my @missing = grep { not param($_) } @param_names;

if ( param('submitted') and @missing ) {
    print 
        "Please fill in: ", 
        i({-style=>'color:#A00;'},
          serial(@missing) . '.'
        );
}

for my $field ( @param_names  ) {
    print p(
            b($field),
            textfield(-name => $field )
            );
}

print submit(-name=>'submitted');
print end_form(), end_html();

exit 0;
#=========================================================
sub serial {
    join(', ', @_[0..$#_-1]) . 
        (@_>2 ? ',':'' ) . 
        (@_>1 ? (' and ' . $_[-1]) : $_[-1]);
}
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