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Boris Likhobabin
3,581 PointsWhat is a concrete type in swfit and what is the opposite of that?
Can someone please elaborte. Teachers keep using this word in almost every video and I don't remeber them defining it properly.
2 Answers
David Lin
35,864 PointsI have a better answer ...
Concrete types are structs, classes, and enums which adopt protocols and provide concrete values and implementations for the required properties and functions.
In contrast, protocols are not concrete types, because they simply define an interface which specifies what properties and functions are required, but without specifying any concrete values or implementations for them.
David Lin
35,864 PointsAre you referring to generics? For example, [T] is generic, because "T" can refer to any type, so the array can consist of any type. But [String] is concrete, because the array is specified to consist of elements of only the type String.