xcode - Swift: filter protocol array by comparing types -


(first post)

usually im able find answers here or elsewhere no luck time =(

question: in swift, how filter array of protocol type implementing type supplied function parameter?

protocol aprotocol {    var number:int { set } }  class aclass: aprotocol {     var number = 1 }  class anotherclass: aprotocol {     var number = 1 }  var array:[aprotocol] = [ aclass(), anotherclass(), aclass() ]  func foo (parameter:aprotocol) -> int {     return array.filter({ /* p in p.self == parameter.self  */ }).count }  var bar:aprotocol = // aclass() or anotherclass()  var result:int = foo(bar) // should return 2 or 1, depending on bar type

maybe not right approach @ all?

thanks!

here think want:

return array.filter { (element: aprotocol) -> bool in     element.dynamictype == parameter.dynamictype }.count

but recommend this, same, without useless instance of aclass() passed in answer on top. way faster:

func foo <t: aprotocol>(type: t.type) -> int {     return array.filter { (element: aprotocol) -> bool in         element.dynamictype == type     }.count }  var result:int = foo(aclass)

the dynamictype return type of instance


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