What about if we defined subclasses with the “subclass” keyword instead of “class”? So you knew the first parameter was always going to be a base class?
That way we keep the single “:” everywhere else - where clauses, generic constraints lists, etc. > On 22 Jul 2016, at 15:14, Vladimir.S via swift-evolution > <[email protected]> wrote: > > I remember that this was discussed, but can't find any decision regarding > this.. So, as a last chance, don't we want in Swift 3.0, as big source > breaking change, separate class inheritance and protocol conformance in > syntax? > > Sorry if there was a decision about this suggestions. Please let know in this > case. > > I.e. when I see the following I can't understand if the class inherits from > base class and conforms to protocols or just conforms to two protocols: > > class MyClass : First, Second, Third { > } > > We don't have a rule to name protocols with 'Protocol'/other suffix/prefix, > or classes with 'T'/'C' prefix or something like this, so I believe to > improve the clarity of code we should separate in syntax inheritance and > conformance. > > As I understand we should discuss changes in these areas: > > 1. class inheritance : > class Child: BaseClass > > 2. class conformance : > class Child: SomeProtocol1, SomeProtocol2 > > 3. class inheritance + conformance : > class Child: BaseClass, SomeProtocol1, SomeProtocol2 > > 4. protocol conformance for structs: > struct Struct: SomeProtocol1, SomeProtocol2 > > 5. protocol inheritance: > protocol Child: BaseProtocol1, BaseProtocol2 > > > My suggestions: > > I) separate inheritance with double colon : > > 1. class inheritance : > class Child:: BaseClass > > 2. class conformance : > class Child: SomeProtocol1, SomeProtocol2 > > 3. class inheritance + conformance : > class Child:: BaseClass : SomeProtocol1, SomeProtocol2 > > 4. protocol conformance for structs: > struct Struct: SomeProtocol1, SomeProtocol2 > > 5. protocol inheritance: > protocol Child:: BaseProtocol1, BaseProtocol2 > > > II) in class definition use parenthesis to separate inheritance and > conformance : > > 1. class inheritance : > class Child: BaseClass > > 2. class conformance : > class Child: (SomeProtocol1, SomeProtocol2) > > 3. class inheritance + conformance : > class Child: BaseClass (SomeProtocol1, SomeProtocol2) > > 4. protocol conformance for structs: > struct Struct: SomeProtocol1, SomeProtocol2 > or > struct Struct: (SomeProtocol1, SomeProtocol2) > should be discussed > > 5. protocol inheritance: > protocol Child: BaseProtocol1, BaseProtocol2 > > > III) special word like 'conforms' > > 1. class inheritance : > class Child: BaseClass > > 2. class conformance : > class Child: conforms SomeProtocol1, SomeProtocol2 > or > class Child conforms SomeProtocol1, SomeProtocol2 > > 3. class inheritance + conformance : > class Child: BaseClass conforms SomeProtocol1, SomeProtocol2 > > 4. protocol conformance for structs: > struct Struct: conforms SomeProtocol1, SomeProtocol2 > or > struct Struct conforms SomeProtocol1, SomeProtocol2 > > 5. protocol inheritance: > protocol Child: BaseProtocol1, BaseProtocol2 > > > Thoughts? > _______________________________________________ > swift-evolution mailing list > [email protected] > https://lists.swift.org/mailman/listinfo/swift-evolution _______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
