[nine_k]

I wonder if the culture of "Optional" with ".and_then" / ".or_else" has any foothold in the Ruby or Crystal communities. Functional approach is so much simpler and more elegant; with Ruby's blocks, it can be made to also look natural.

With promises and things like array.map being widely accepted in e.g. JS community, I'd hazard to say that mainstream industrial programming finally starts to embrace the use of monads. It would be great to embrace the most badly missing of them all, Option / Maybe, instead of the "billion dollar mistake" of null. ("Nullable" is a half-step in the right direction.)

[RX14]

I believe that while monads are great, crystal obviates the need for option because String? doesn't mean "nullable string", it means (String | Nil) or "the type which is the union of String and Nil". This is a much more powerful and generic concept than nillable types, as you can call any method in this object which is defined both on String and Nil. One such method (which happens to be defined in every type) is the method try. This is equivalent to a map in monad optional. I'm sure you can see that this generalises to make type unions possible to represent the optional type (with no overhead) and all methods which you could implement on it. Furthermore, its actually more powerful as this is implemented at the type system level, meaning flow typing works, which makes code much cleaner as you can use normal if statements with boolean conjugates to "unwrap" these types (really just removing types from the union) which is cleaner.

[nine_k]

This (chaining "try" calls) is basically what I had hoped would happen :)

It is the "happy path", represented compactly but without a way to forget and step on a nil.