(That is, what's the difference between `as? String` and `as String?`? :simple_smile:)

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[sindrenm]

(That is, what's the difference between as? String and as String?? simple smile)

[diesieben07]

as? String will try to cast to non-null String and give null if not possible (i.e. value is null or something other than String, such as Int).
as String? will cast to nullable String and fail if it's something else (e.g. Int).

[diesieben07]

Fail being ClassCastException

[sindrenm]

But the end result of both operations will always be a String? (unless it fails because it's an Int or whatever)?

[sindrenm]

So something like this will not compile:

("Hello World" as? String).length

[sindrenm]

Due to not checking for null first (i.e. ?.length).

[sindrenm]

Oh!

[sindrenm]

(1337 as? String) // => null

[sindrenm]

Alright, gotcha! Thanks, @diesieben07. simple smile

[diesieben07]

Yes, 1337 as? String is null, 1337 as String? throws ClassCastException

[sindrenm]

Yep, that was the difference! TIL. simple smile