38 lines
873 B
Tcl
38 lines
873 B
Tcl
# Enums
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# Enums define a type with multiple possible variants:
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enum Shape(Circle(radius: Num), Rectangle(width: Num, height: Num), Point):
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# Use `when` to pattern match an enum:
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func area(shape: Shape -> Num):
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when shape is Circle(radius):
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return Num.PI * radius^2
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is Rectangle(width, height):
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return width * height
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is Point:
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return 0
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func main():
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# You can create instances of an enum:
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point := Shape.Point
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# Single member enums display without the field names:
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circle := Shape.Circle(radius=10)
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>> circle
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= Circle(10)
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# Multi-member enums explicitly list their field names:
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rect := Shape.Rectangle(width=4, height=5)
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>> rect
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= Rectangle(width=4, height=5)
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>> point:area()
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= ???
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>> rect:area()
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= ???
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>> "My shape is $circle"
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= ???
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