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Re:Functional exceptionless error-handling with optional and... by haar on Sunday December 03, 2017 @03:21PM (#15839352)
We've been using this style a lot in Elixir via the `with` macro

    def get_cute_cat(image_id) do
      with {:ok, cropped}       <- find_cat(image_id),
           {:ok, with_tie}      <- add_bowtie(cropped),
           {:ok, with_sparkles} <- make_eyes_sparkle(with_tie)
      do
        with_sparkles 
        |> make_smaller() 
        |> add_rainbow()
      end
    end
If any of the values on the rhs of a `<-` cannot be pattern matched, it returns up the returned value. This value can be pattern matched easily inside an `else` clause underneath the main block. The use of the `:ok,` vs `:error,` tuple convention allows multiple values to be destructured and passed around if needed (rather than an optional type).

If you find the code getting unwieldily, as runeks said you can break it down into simpler constructs.

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