I hate to ask a stupid question, but when troubleshooting I always start at the "is it plugged in" basics: Is Mail::Sendmail installed?

Ok!
No, It's not installed, the purpose was to create some "try/catch" code to catch the error if the module isn't installed, since the code is to be distributed to several machines.

You want string eval:

eval "use Some::Module 94.5";
 
if($@) {
  print "Oh noes, it's not installed!\n";
} else {
  ...
}
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@module = ("require Mail::Sendmail 0.75");
for(@module){
        eval;
        if($@){
                $_=~/\w+\W(\S+)/;
                print "Module $1 does not exist, please install it fir
+st!\n";
                }else{
                        #do stuff
                        }
        };
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$module = "bigfloat";
qx(perl -M$module -e 'exit' 2>/dev/null);
print "$module is not installed !!\n" if $? != 0;
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#!/usr/bin/perl

use strict;
use ExtUtils::Installed;

my $check_mod = ExtUtils::Installed->new();
die "File::Find is not installed" unless
  ( grep /File::Find/, $check_mod->modules() );
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I assume what you really want is to provide an option for the program can send mail in one of a few possible ways. Or, not at all, if it's not available. (Note that it's possible that you cannot send mail even though you have the necessary mail modules.)

In that case, I'd write a little wrapper module that tries to load one of a few mail modules, writes down what module to use, and provides a hook to send mail using that module without exposing too much to the client program.

Perhaps you can base that on a module like MIME::Lite, since that already has a way to transparently send mail using one of a few possible modules.

use strict;
use warnings;

use ExtUtils::Installed;

#
# First, check if all the required modules have
# been installed inthe system this script will run on.
#
BEGIN {
    my @import_modules = (
        'Getopt::Lucid',
        'Apache::Htpasswd',
        'IO::CaptureOutput'
        );

    my ($inst) = ExtUtils::Installed->new();
    my (@installed_modules) = $inst->modules();

    for ( @import_modules ) {

        eval{ $inst->validate($_) };
        if($@) {
            print qq{\n
Module $_ does not seem to be installed in this system.
Please install the module and try again!\n
};
            exit 1;

        } # end 'if'

    } # end 'for'

} # end 'BEGIN' block
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