Mix Deps.Add

[andyl]

From twitter:

@hauleth Unfortunately, even with this, implementing mix deps.add in a foolproof way is impossible.

• what if :deps is list within config/0?
• what if it is module attribute instead of function?
• what if there is no :deps key in config/0
• what if :deps call function defined in another file?

Due to fact that mix.exs is executable it is hard.

That would be good enough for an external library then. Built in tool should work in 100% of the cases.

@AmNicd I don't agree. You can make it bail out and give a good error message explaining why. If you've moved your deps away from the default, you're already probably experienced enough to deal with it. This is letting niche use cases prevent usability improvements from the majority.