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Equality on Objective-C typedef enum in Swift

Tags:

enums

swift

I'm working with the Facebook Objective-C SDK in Swift and I'm trying to compare an FBSessionState value with a value from the enum. However I get the compiler error:

Could not find an overload for '==' that accepts the supplied arguments

I'm essentially trying to accomplish:

if state == FBSessionStateOpen { ... }

I'm able to work around this by comparing against the value...

if state.value == FBSessionStateOpen.value { ... }

But I'm wondering if there is a way to make this work more like a Swift enum?

like image 244
Denny Ferrassoli Avatar asked Jun 10 '14 06:06

Denny Ferrassoli

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3 Answers

You could unwrap the enum and constants with '.value' to get the underlying integer, which should be switchable:

switch x.value {
  case Foo.value:
}

Maybe this is a bug and apple fix it in future releases.

like image 134
Nikolai Nagornyi Avatar answered Oct 01 '22 14:10

Nikolai Nagornyi

With the Beta4 update, the .value workaround no longer works. There doesn't seem to be another easy workaround without changing Facebook's SDK.

I changed all the Facebook enums to use the NS_ENUM macro, so that you can use Swift syntax the enums.

if FBSession.activeSession().state == .CreatedTokenLoaded

These changes were merged into pgaspar's Facebook fork, which includes other fixes for Swift compatibility.

pod 'Facebook-iOS-SDK', :git => 'https://github.com/pgaspar/facebook-ios-sdk.git'
like image 21
lsw Avatar answered Oct 01 '22 12:10

lsw

Adding to Nikolai Nagorny's answer, this is what worked for me:

if (device.deviceType.value == TYPE_BLUETOOTHNA.value)
like image 38
Vincil Bishop Avatar answered Oct 01 '22 12:10

Vincil Bishop
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