Hello O Glorious Monks!

I'm attempting to include some code in my script that will automatically take care of the installation of the modules I require without user intervention. This will make the initial installation of this script much simpler (it is for in-house use, but will be distributed to many servers).

I've done the following:

#!/usr/local/bin/perl -w

use strict;

print "You must be root to run this program\n" and exit 1 unless ($> =
+= 0);

BEGIN {
    unless (eval { require Config::Auto }) {
        print "Need to install Config::Auto module.  I'll do that for 
+you now:\n";
        my $ret = system("perl -MCPAN -e 'install Config::Auto'");
        print $ret;
    }
}
[download]

and all has gone as planned. Horray! The problem is, what I want to do is the following:

#!/usr/local/bin/perl -w

use strict;

print "You must be root to run this program\n" and exit 1 unless ($> =
+= 0);

BEGIN {
    foreach my $module ( qw{Config::Auto Mail::Sendmail} ) {
        unless (eval { require $module }) {
            print "Need to install $module module.  I'll do that for y
+ou now:\n";
            my $ret = system("perl -MCPAN -e 'install $module'");
            print $ret;
        }   
    }   
}
[download]

but for some reason, the eval is returning false even though the modules do exist, and forcing my cpan installation to be attempted again.

AHA!! I just figured it out, after re-reading perldoc -f require. I'll post the question anyways in the hopes of enlightening someone in the future that may run into the same issue. The trick is:

eval {"require $module"}
[download]

Which I somehow glossed over on my first reading of the perldoc. I'm glad I figured it out!

I guess I'll change the question to this: Does anyone feel this is a good or bad design decision to do this type of auto-installation for a script? Should I attempt to make the installation portion interactive, perhaps prompting the user as to whether or not they really want to install the modules?

Thanks for your time...

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