Introduce a :or type

[whatyouhide]

It's missing docs still, but I think this is a pretty low hanging fruit. Reasons why I'm okay with this:

• the error message comes out nicely by combining all the error messages
• "casting" works okay by just casting as the first matching type
• I've used this a billion times through {:custom, ...} in my code already eheh

Thoughts before I write docs? :)

[josevalim]

Sounds good to me! I am just not sure if :or is the best name. As it can cause confusion with one_of. Not sure of suggestions though.

[whatyouhide]

@josevalim I know, it should be one_of for this feature and member_of for what today is called one_of 😭 Maybe we can call this :alternatives, not sure 😕

[josevalim]

I think it is fine to name this or if we name the one member_of or in. Maybe we can deprecate one_of as in.

[whatyouhide]

@josevalim I think the clearest options are:

• call this :one_of
• call the other one :member_of

If that's fine, I propose to:

1. Rename :one_of to :member_of with warning
2. Call this :or for now

In the next release, we can rename :or to :one_of if we want to, and call it a day. Thoughts?

[josevalim]

I would prefer to not do a double renaming. Which is why I went with in/or. In is also a common idiom in Elixir. I think anything starting with one_of will be ambiguous

[whatyouhide]

Okay, lets go with in and or 🙃

[whatyouhide]

@josevalim ready for another review :)