Version dependencies: Refactor dependency checks into sharable helper functions

I'd suggest something like this (pseudo code), (no idea what to call it)

function system_version_check($current_version, $requires = array()) {
  foreach ($requires as $required_version) {
    if ((isset($required_version['op']) && !version_compare($current_version, $required_version['version'], $required_version['op'])) ||
        (isset($required_version['preg']) && !preg_match($required_version['preg'], $current_version))) {
    return FALSE;
  }
  return TRUE;
}

Also on the list, perhaps, moving the parsing out of _module_build_dependencies(), so that it can be reused for themes?

Refactored. Allowed me to move back the two other (enabled, disabled) messages to the same level. might be curious to use module_check_incompatibility instead of compatibility but that's what I needed. Also, simplified: removed the preg, now we check everything with version_compare. Sometimes two, but still, the code is simpler. It works.

Looks great.

I don't fully understand the return value of module_parse_dependency(). Why is the original value returned at all? I'd change that as it would make for a more predictable and consistent API.

The PHPdoc doesn't properly explain what is returned. Maybe you can include an example?

Although that structure is documented, it does not matter at all. You pass the structure on to module_check_incompatibility and that's it.

Well, sure. Cleaner a bit, I guess.

Yes because you added a 'name' key to my otherwise nice and empty array. Anyways, dww happy, the bot is happy and I am OK too.

Since documentation of the return value is all Dries pointed out above (curiously, not also the wtf-inducing "$v" as a parameter in a public function), and the documentation looks good, I committed this to HEAD.