> Can't quite see where "Inheritance for structs / "newtype"-feature"
> enables this, however. Care to explain?
It's not required, but unless you want to implement a completely new numeric
type (like fractions), it is tedious to declare all operations and conversions
that are useful or required:
struct CustomDouble {
let value: Double
}
func == (a: CustomDouble, b: CustomDouble) -> Bool {
return abs(a.value - b.value) < 0.01
}
This type can handle the comparison, but actually, you don't want a struct that
contains a double, but that is a double (and inherits all abilities of this
type).
Greg Titus already did some research and made the observation that such simple
container-types have no memory or performance penalty, but as a developer, you
have to write many stupid functions that do nothing but forwarding operations
on x to x.value…
Tino_______________________________________________
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