35 lines
908 B
Pony
35 lines
908 B
Pony
primitive Red
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primitive Blue
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primitive Green
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// Let Colour be an alias for the union type (Red | Blue | Green)
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type Colour is (Red | Blue | Green)
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// ColourList is a constant representing the union type
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primitive ColourList
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fun apply(): Array[Colour] =>
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[Red; Green; Blue]
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actor Main
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new create(env: Env) =>
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for colour in ColourList().values() do
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env.out.print("I should be printing a colour
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but I don't know how to cast to string")
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end
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// Type aliases can also be used to give simpler names to complex types
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interface HasName
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fun name(): String
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interface HasAge
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fun age(): U32
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interface HasFeelings
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fun feeling(): String
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// Let Person be an alias for the intersection of those three types
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// This makes it easier to refer to
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type Person is (HasName & HasAge & HasFeelings)
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// You can do this with traits as well as interfaces.
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