Menu
Is there an equivalent syntax or technique for Anonymous class in Swift? Just for clarification Anonymous class in Java example here - http://docs.oracle.com/javase/tutorial/java/javaOO/anonymousclasses.html
Thanks!
214
Simply use a struct for defining the interface via function values and then anonymously implement it from a function, as is a very common way to write objects in JavaScript. The function is only required for creating a private scope for the object returned.
Anonymous classes enable you to make your code more concise. They enable you to declare and instantiate a class at the same time. They are like local classes except that they do not have a name. Use them if you need to use a local class only once.
A nested class that doesn't have any name is known as an anonymous class. An anonymous class must be defined inside another class. Hence, it is also known as an anonymous inner class. Its syntax is: class outerClass { // defining anonymous class object1 = new Type(parameterList) { // body of the anonymous class }; }
An anonymous class cannot define any static fields, methods, or classes, except for staticfinal constants. Interfaces cannot be defined anonymously, since there is no way to implement an interface without a name. Also, like local classes, anonymous classes cannot be public, private, protected, or static.
There is no equivalent syntax, as far as I know.
Regarding equivalent techniques, theoretically you could use closures and define structs and classes inside them. Sadly, I can't get this to work in a playground or project without making it crash. Most likely this isn't ready to be used in the current beta.
Something like...
protocol SomeProtocol { func hello() } let closure : () -> () = { class NotSoAnonymousClass : SomeProtocol { func hello() { println("Hello") } } let object = NotSoAnonymousClass() object.hello() } ...currently outputs this error:
invalid linkage type for global declaration %swift.full_heapmetadata* @_TMdCFIv4Test7closureFT_T_iU_FT_T_L_19NotSoAnonymousClass LLVM ERROR: Broken module found, compilation aborted! Command /Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift failed with exit code 1 If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
