How to declare “throws” for `subscript(dynamicMember:)`in @dynamicMemberLookup in swift?
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When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
asked Nov 15 at 17:53
leavez
89121123
add a comment |
up vote
0
down vote
favorite
When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
asked Nov 15 at 17:53
leavez
89121123
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 at 18:02
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
asked Nov 15 at 17:53
leavez
89121123
When using @dynamicMemberLookup in swift, subscript cannot declare a "throws".
subscript(dynamicMember member: String) -> Any
This is OK.
subscript(dynamicMember member: String) throws -> Any
This will give a compile error.
swift subscript throws
swift subscript throws
asked Nov 15 at 17:53
leavez
89121123
asked Nov 15 at 17:53
leavez
89121123
asked Nov 15 at 17:53
leavez
89121123
asked Nov 15 at 17:53
leavez
89121123
asked Nov 15 at 17:53
leavez
89121123
89121123
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 at 18:02
add a comment |
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 at 18:02
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 at 18:02
Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 at 18:02
add a comment |
1 Answer
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up vote
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down vote
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A {
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
}
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 at 18:06
leavez
89121123
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A {
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
}
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 at 18:06
leavez
89121123
add a comment |
up vote
0
down vote
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A {
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
}
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 at 18:06
leavez
89121123
add a comment |
up vote
0
down vote
up vote
0
down vote
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A {
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
}
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 at 18:06
leavez
89121123
Using throws in subscript is not supported by the language right now. However you can use some tricks to avoid that, meanwhile, keep the feature of throws:
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
Just declare the subscription return an block, then add a () behind the function to execute the real function. So you could code like this:
@dynamicMemberLookup
class A {
public subscript(dynamicMember member: String) -> () throws -> Any {
return { try REAL_FUNCTION_THAT_THROWS() }
}
}
let a = A()
let value = try? a.doWhatYouWant()
let value2 = try? a.anotherMethod()
answered Nov 15 at 18:06
leavez
89121123
answered Nov 15 at 18:06
leavez
89121123
answered Nov 15 at 18:06
leavez
89121123
answered Nov 15 at 18:06
leavez
89121123
89121123
add a comment |
add a comment |
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Swift doesn't yet support throwing subscripts or computed properties in general. Here's a relevant thread discussing what the semantics of such declarations would be: forums.swift.org/t/….
– Hamish
Nov 15 at 18:02