Validate conformance object to protocol with associated type
0
This is my code:
protocol Protocol {
associatedtype A
}
class Class: Protocol {
typealias A = Int
}
assert(type(of: Class()) == Protocol.self)
The error is ofcourse:
Protocol 'Protocol' can only be used as a generic constraint because
it has Self or associated type requirements
I understand the error, but I hope there is some way to check if a given object conform to a protocol with an associated type, without the need of binding/casting.
swift protocols swift-protocols
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
add a comment |
0
This is my code:
protocol Protocol {
associatedtype A
}
class Class: Protocol {
typealias A = Int
}
assert(type(of: Class()) == Protocol.self)
The error is ofcourse:
Protocol 'Protocol' can only be used as a generic constraint because
it has Self or associated type requirements
I understand the error, but I hope there is some way to check if a given object conform to a protocol with an associated type, without the need of binding/casting.
swift protocols swift-protocols
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
I don't think it's possible. The issue is thatProtocolisn't one type. It's a template for a type, where one type exists for every possible value ofA.
– Alexander
Nov 25 '18 at 12:14
@Alexander Maybe with reflection? I can't work it out though with Mirror...
– J. Doe
Nov 25 '18 at 13:43
Swift doesn't really have many reflection capabilities yet. The meta data necessary to do that at run time exists, and it's used by the debug tools, but an API hasn't been built to expose it yet. They're prioritizing ABI stability first.
– Alexander
Nov 25 '18 at 19:33
add a comment |
0
0
0
This is my code:
protocol Protocol {
associatedtype A
}
class Class: Protocol {
typealias A = Int
}
assert(type(of: Class()) == Protocol.self)
The error is ofcourse:
Protocol 'Protocol' can only be used as a generic constraint because
it has Self or associated type requirements
I understand the error, but I hope there is some way to check if a given object conform to a protocol with an associated type, without the need of binding/casting.
swift protocols swift-protocols
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
This is my code:
protocol Protocol {
associatedtype A
}
class Class: Protocol {
typealias A = Int
}
assert(type(of: Class()) == Protocol.self)
The error is ofcourse:
Protocol 'Protocol' can only be used as a generic constraint because
it has Self or associated type requirements
I understand the error, but I hope there is some way to check if a given object conform to a protocol with an associated type, without the need of binding/casting.
swift protocols swift-protocols
swift protocols swift-protocols
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
asked Nov 25 '18 at 11:12
J. DoeJ. Doe
3,01711133
3,01711133
I don't think it's possible. The issue is thatProtocolisn't one type. It's a template for a type, where one type exists for every possible value ofA.
– Alexander
Nov 25 '18 at 12:14
@Alexander Maybe with reflection? I can't work it out though with Mirror...
– J. Doe
Nov 25 '18 at 13:43
Swift doesn't really have many reflection capabilities yet. The meta data necessary to do that at run time exists, and it's used by the debug tools, but an API hasn't been built to expose it yet. They're prioritizing ABI stability first.
– Alexander
Nov 25 '18 at 19:33
add a comment |
I don't think it's possible. The issue is thatProtocolisn't one type. It's a template for a type, where one type exists for every possible value ofA.
– Alexander
Nov 25 '18 at 12:14
@Alexander Maybe with reflection? I can't work it out though with Mirror...
– J. Doe
Nov 25 '18 at 13:43
Swift doesn't really have many reflection capabilities yet. The meta data necessary to do that at run time exists, and it's used by the debug tools, but an API hasn't been built to expose it yet. They're prioritizing ABI stability first.
– Alexander
Nov 25 '18 at 19:33
I don't think it's possible. The issue is that
Protocol isn't one type. It's a template for a type, where one type exists for every possible value of A.– Alexander
Nov 25 '18 at 12:14
I don't think it's possible. The issue is that
Protocol isn't one type. It's a template for a type, where one type exists for every possible value of A.– Alexander
Nov 25 '18 at 12:14
@Alexander Maybe with reflection? I can't work it out though with Mirror...
– J. Doe
Nov 25 '18 at 13:43
@Alexander Maybe with reflection? I can't work it out though with Mirror...
– J. Doe
Nov 25 '18 at 13:43
Swift doesn't really have many reflection capabilities yet. The meta data necessary to do that at run time exists, and it's used by the debug tools, but an API hasn't been built to expose it yet. They're prioritizing ABI stability first.
– Alexander
Nov 25 '18 at 19:33
Swift doesn't really have many reflection capabilities yet. The meta data necessary to do that at run time exists, and it's used by the debug tools, but an API hasn't been built to expose it yet. They're prioritizing ABI stability first.
– Alexander
Nov 25 '18 at 19:33
add a comment |
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I don't think it's possible. The issue is that
Protocolisn't one type. It's a template for a type, where one type exists for every possible value ofA.– Alexander
Nov 25 '18 at 12:14
@Alexander Maybe with reflection? I can't work it out though with Mirror...
– J. Doe
Nov 25 '18 at 13:43
Swift doesn't really have many reflection capabilities yet. The meta data necessary to do that at run time exists, and it's used by the debug tools, but an API hasn't been built to expose it yet. They're prioritizing ABI stability first.
– Alexander
Nov 25 '18 at 19:33