CGI.pm: HTML comment in <head>

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

I'm trying to insert an HTML comment in the head tag of a doc generated by CGI.pm, but I'm getting and error and I can't see what I'm doing wrong.

#!/usr/local/perl-5.8.7/bin/perl -T
use warnings;
use strict;
use CGI;
use CGI::Carp qw/fatalsToBrowser warningsToBrowser/;
my $query = new CGI;
print $query->start_html( 
        -head=>comment('commentary in the <head>'),
);
print $query->end_html;
[download]

gives

<h1>Software error:</h1>
<pre>Undefined subroutine &amp;main::comment called at /usr/local/apac
+he-1.3.33/cgi-bin/tryCommentInHead.cgi line 7.
</pre>
<p>
For help, please send mail to this site's webmaster, giving this error
+ message 
and the time and date of the error.
 
</p>
[Mon Aug 14 15:00:08 2006] tryCommentInHead.cgi: Undefined subroutine 
+&main::comment called at /usr/local/apache-1.3.33/cgi-bin/tryCommentI
+nHead.cgi line 7.
[download]

Comment on CGI.pm: HTML comment in <head> Select or Download Code

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Re: CGI.pm: HTML comment in <head> by friedo (Prior) on Aug 14, 2006 at 20:12 UTC
The error message you're getting is telling you that the subroutine `&main::comment` is undefined, which is true, because you're not importing the function from CGI.pm. To do that, you need to do: `use CGI qw/:standard/;` [download] But it looks like you're planning to use the OO style instead, so instead of importing, you can just use `$query->comment()` instead of `comment()`.	[reply] [d/l] [select]
Re^2: CGI.pm: HTML comment in <head> by andyford (Curate) on Aug 14, 2006 at 20:21 UTC
Right, of course. End day now.	[reply]
Re: CGI.pm: HTML comment in <head> by Fletch (Bishop) on Aug 14, 2006 at 20:12 UTC
As the error message says, you're trying to call an undefined subroutine. Since you didn't import `comment` from CGI explicitly (or via a tag like `:standard`) you need to call it as a method on your `$query` instance instead: `$query->comment( "OMGWTFBBQ?" )` Update: Gah, the tag's `:standard` not `:common`.	[reply] [d/l] [select]