comment on

You can check for the existence of a module with eval:

eval "use Some::Module"; 
$@ && print_an_error_message_with_a_nice_link_to_cpan();
[download]

Here's another technique for using non-core modules that fits in better with the other module calls, and is able to report multiple missing modules:

#!/usr/bin/perl -w

use strict;
use CGI ':standard';
use_('Some::Module');
use_('Some::OtherModule');

install_modules() if %_; # if use_ fails this happens

sub use_
{
eval "use $_[0]";
$@ && $_{$_[0]}++;
undef $@
}

sub install_modules
{ # link to dist(s) on cpan
if(keys %_ > 1){ $_ = 's' } else { $_ = '' }

my $p = header;
$p .= qq~Required perl module$_ not found: ~;

for(keys %_){
    $p .= qq~<a href='http://search.cpan.org/search?dist=$_'>$_</a>, ~
+;
    }
$p =~ s|, $||;
print $p;
exit
}
[download]

Hope this helps.

Update: Cleaned it up a bit.

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In reply to Re: Checking for PERL Modules by epoptai
in thread Checking for PERL Modules by kidd

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