What's the underlying model here?

You have to consider the full CPAN object model. Ultimately, actions all fall to a CPAN::Distribution object and "force" is just a method that sets a flag and invokes other methods. The shell is a CPAN::Shell object that converts your commands to actions upon the appropriate objects.

For example, installing a module means creating a module object, finding the distribution object that corresponds to it, and then installing the distribution. (Well, that's the short version anyway.)

Here's a modified excerpt of what I use in Perl::Dist as part of building Vanilla Perl. (Warning: Perl::Dist as a whole sucks and needs to be rewritten; but using snippets is OK.)

print "Preparing to install $name from CPAN\n";

$obj = CPAN::Shell->expandany( $name ) 
    or die "CPAN.pm couldn't locate $name";

if ( $obj->uptodate ) {
    print "$name is up to date\n";
    exit
}

if ( $force ) {
    $obj->force("install");
    $obj->uptodate 
        or die "Forced installation of $name appears to have failed";
}
else {
    $obj->install;
    $obj->uptodate 
        or die "Installation of $name appears to have failed";
}
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The "force" command takes as a first argument the method to invoke (currently: "make", "test", or "install") and executes the command from scratch.
...
CPAN::Distribution::force($method,@args)

Forces CPAN to perform a task that normally would have failed. Force takes as arguments a method name to be called and any number of additional arguments that should be passed to the called method. The internals of the object get the needed changes so that CPAN.pm does not refuse to take the action.

So you probably have to say

force('install','SQL::Translator');
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CPAN shell commands are method invocations, basically - shellish perl ;-)

--shmem

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}