Misleading error when an old version of a package is installed

[sporto]

If I have a project which has an older version of a package elm make will fail giving an error related to wrong usage e.g.

elm-package say that packageX should be 2.1, but version 2.0 is installed in my system. This happens because someone else updated packageX in elm-package. Then when running elm-make I see:

Cannot find variable `PackageX.foo`.

68|     PackageX.foo

`PackageX` does not expose `foo`. 

Where foo was introduced in 2.1 of that package.

So I think that there is some problem with our app. But the real problem is that I haven't installed the updated package.

It would be great if elm make could give me an error like: "elm-package requires packageX 2.1, you have installed 2.0`

[process-bot]

Thanks for the issue! Make sure it satisfies this checklist. My human colleagues will appreciate it!

Here is what to expect next, and if anyone wants to comment, keep these things in mind.