swift - CGEventTap, CGEvent & NSEvent Memory Leak -

i'm having tough time releasing cgevent once convert nsevent (which need). i'm doing using cgeventtap. documentation states

returns: autoreleased nsevent object equivalent cgevent

the returned object retains cgeventref object (cgevent) until (the objective-c object) freed—it releases cgeventref object. if no cocoa event corresponds cgeventref object, method returns nil.

so have written code convert nsevent , set nsevent nil (as test). after setting nil, either nsevent or cgevent not released , memory keeps going every mouse move. i'm not entirely sure why. feel i'm missing fundamental here.

here's code.

func eventcallback(proxy: cgeventtapproxy, type: cgeventtype, var event: cgevent, refcon: unsafemutablepointer<void>) -> unmanaged<cgevent>? {      //this line causes memory leak     if var e: nsevent? = nsevent(cgevent: event) {         e = nil //according docs, should decrease reference count event     }      return unmanaged.passunretained(event!) } 

as @willeke commented, autoreleasepool fixed memory leak me.

swift should automatically cleaning nsevents you, setting e nil shouldn't necessary inside autoreleasepool.

here's worked me:

func eventcallback(proxy: cgeventtapproxy, type: cgeventtype, var event: cgevent, refcon: unsafemutablepointer<void>) -> unmanaged<cgevent>? {    autoreleasepool{      var e: nsevent? = nsevent(cgevent: event)     // code using e   }    return unmanaged.passunretained(event) }