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Comment by andrepd | Hacker News Reader

In OCaml:

    module Foo = struct
      let first = 1
      let second = 2
      let third = 3
    end

    module Bar = struct
      include Foo    (* Include contents of [Foo] *)
      let third = 4  (* Override [third] *)
    end

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OCaml has real objects and classes. Moreover, it is trivial to demonstrate that your example doesn't work in practice:

  module Foo = struct
   let first() = 1
   let second() = first() + 1
  end

  module Bar = struct
    include Foo
    let first() = 0
  end

Bar.second () will still be 2 because of static binding. Thus you cannot use this approach to replace 'first' by itself without creating inconsistencies.

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