Foldable operations on Project

[pepegar]

This PR:

• Introduces some Foldable like operations on Project typeclass
• Creates syntax for those
• Introduces a simple type tagging case class @@ if agreed, it can be substituted with a proper newtypes library like https://github.com/julien-truffaut/newts or https://github.com/alexknvl/newtypes
• creates two newtypes for boolean (conjunction & disjunction)
• creates Eq & Monoid instances for T: Basis[ListF, ?]

[andyscott]

This is pretty great! I'm 👍 for the tagged types as you've implemented them. I have a few notes/discussion items regarding organization before we merge.

[andyscott]

Alright! Prepare for a brain dump of some of my overall thoughts on Droste's design 😄:

My biggest ask (or complaint?) is that I'd like all functions in Droste to delegate to "static" functions on helper objects or in package objects that perform the specific operation. These static methods should always exist-- that is to say that you don't need to summon an implicit value and call the method on said value. Methods on implicit values are allowed, but they must statically delegate to an identically named method. This is absolutely a design decision on my part, and is perhaps worth a proper discussion in a separate issue.

In this case, for example, I'd like to see some kind of foldable helper object that has all, any, collect, contains, etc implementations. The functions on the Project type class would simply delegate to these static functions. It's boilerplate, which is ugly, but I like having all core functionality implemented in the most straightforward and least magical way possible.

If you need this functionality ASAP, feel free to merge as is-- the value of this new functionality outweighs blocking the PR.

[pepegar]

I like the idea @andyscott. I'll update the PR to be able to merge soon :)

[pepegar]

OK, so I've ended up moving de implementation of those functions to the Project companion, since that's where I think it belongs (even though they're like traverse operations), and because I prefer not to clutter the project with top level objects ;)

[andyscott]

Awesome!