[jhc] flag to compile a single module?

I was just thinking that it would be great jhc would compile just a single module (and its dependencies, of course) when that module was requested (instead of complaining about a lack of a main function). This would be handy for testing, but also could enable parallel builds, assuming that jhc won't trash the ho cache if two builds are run simultaneously (which is important anyhow... e.g. if building two versions of the same code at the same time). I'm imagining one could just request either a module or a hs file: jhc Foo.Bar or jhc Foo/Bar.hs Or am I missing something and is this already possible? David