Typing Lists and Tuples in Elixir

Re:Typing Lists and Tuples in Elixir by greener_grass on Wednesday August 28, 2024 @02:48PM (#41382847)

NonEmptyList<'t> has a method Uncons that returns 't * List<'t>

List<'t> has a function TryUncons that gives Option<'t * List<'t>>

List<'t> does not have a method Uncons.

We can define TryUncons for NonEmptyList<'t> in terms of Uncons, specifically:

    this.TryUncons() = 
      this.Uncons() 
      |> Some

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Re:Typing Lists and Tuples in Elixir by jerf on Wednesday August 28, 2024 @04:18PM (#41383818)

I didn't spell it out adequately, only implied it, but I am talking about a fully loaded List, not one that just barely works, e.g., it has filter, it has all the other things you'd expect from a List. I did discuss the "just barely works" case at the end.

It would be an odd "object oriented language" list that lacked such things, e.g., https://docs.oracle.com/javase/8/docs/api/java/util/List.htm... . We're in OO land here, not FP land.

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