[swift-users] Can I do dynamic casting?

[Johan Segerfeldt]

Zhaoxin,

You are trying to cast to a type which is defined by a variable at runtime.
Casting with `as` is done at compile-time. The variable has no defined value at this time.

The compiler cannot infer what the value of a variable is going to be.
It can only infer types by static analysis.


Regards
Johan

> Is that possible to do dynamic casting?
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> My code:
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>> importFoundation
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>> letarray = [1,2,3,4,5]
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>> letdictionary:[String:Any] = ["numbers":array]
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>> ifletvalue =dictionary["numbers"] {
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>> lettype = type(of: value)
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>> print(type)// Array<Int>
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>> letnumbers = valueas!Array<Int>// [1, 2, 3, 4, 5]
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>> //let numbers2 = value as! type // error: use of undeclared type 'type'
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>> }
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> As you can see, the dynamic casting leads an error. Is there a way to do this? Thanks.
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> Zhaoxin
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