values: prepend superclass values

[gi]

When enumerating values for a subclass, the superclass values are prepended.

Fixes #27.

class A
  include Ruby::Enum
  define :X, 'X'
end

class B < A
  define :Y, 'Y'
end

B.values() == [B::X, B::Y]

[dblock]

Thanks!

• update CHANGELOG
• bump version to 0.9.0
• document values behavior in README

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• increment version in version.rb
• I think because we're changing behavior here in significant ways, I think we need an UPGRADING file, ala https://github.com/slack-ruby/slack-ruby-client/blob/master/UPGRADING.md

More comments below.

[gi]

I think because we're changing behavior here in significant ways, I think we need an UPGRADING file

Could this just go into the changelog? I worry that the UPGRADING file is going to look exactly like the CHANGELOG. Perhaps, for this simple case, a "Breaking Changes" section in the changelog version's entry?

What did you have in mind for the content?

[dblock]

I think because we're changing behavior here in significant ways, I think we need an UPGRADING file

Could this just go into the changelog? I worry that the UPGRADING file is going to look exactly like the CHANGELOG. Perhaps, for this simple case, a "Breaking Changes" section in the changelog version's entry?

This is more of a convention thing from dozens of projects - sometimes these get very long and full of before/after examples, so we haven't been putting long explanations about upgrading into changelog.

What did you have in mind for the content?

I think something like enum classes now inherit values, for example ... with before: and after: output. Keep the format similar to the UPGRADING.md I linked

(thank you)

[dblock]

The example is super clear, this works.

I do have a question. In the scenario with colors inheritance is the wrong object oriented pattern to use. Rainbow colors don't "inherit" primary colors, they are a combination of primary colors and other colors. In this case we would want a module and mixins. Should we allow class PrimaryColors be module PrimaryColors, extend Ruby::Enum, then include PrimaryColors into RainbowColors or something like that? ... for another PR.

Maybe there's a better OOO example for README that we can use in a separate update? WDYT?

[gi]

Yeah. Semantically, it makes more sense to include the PrimaryColors in the RainbowColors class instead of inheriting them.

Though, I see this is a minor implementation detail. Defining an enum doesn't actually create an instance of that class: Colors::RED isn't an instance of Ruby::Enum or Colors. It's a String or Symbol.

There's little difference between inheriting from a class and including a module other than the Ruby semantics. Both options include the base/included class in the class hierarchy.

Regardless, I think this could be an update for another PR.

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100%

[dblock]

Merged, thank you! Do you want to help out with maintenance of this gem @gi? Maybe make the next release. If yes, email dblock[at]dblock[dot]org with your rubygems username/email and I'll add you.