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Comment by wycliffb | Hacker News Reader

Will commence working on a doc to explain some design choices, and what some non-obvious code fragments do; will update here when I commit. There's no subtyping being done currently. The 'match type' construct matches the type of an expression at compile time. I should also add that some design choices may be reviewed before the first release.

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Surely if match type is compile time and there is no subtyping then it is basically a no-op type assert. I.e. it’s like writing (e : t) in ML?

Or is it supposed to allow for some kind of ad-hoc polymorphism like:

  func foo(x) string {
    match type(x) {
      char** : return “an array of strings”
      int : return “a number”
      default : return “not sure”
    }
  }

And this gets transformed into something like:

  func foo(Type x_t, x_t x) string {
    match(x_t) {
      pointer_t(pointer_t(char_t)) : return ...
      ...
    }
  }

Interesting suggestion! Will be sure to add that when I can.

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