Debouncer with Argument

DebouncerPlayground.swift

import Foundation

// Debouncer
func debounce(delay: TimeInterval, action: @escaping (String)->Void) -> (String)->Void {
    let callback = DebounceCallback(action)
    var timer: Timer?
    return { arg in
        if let timer = timer { timer.invalidate() } // invalidate the last timer
        timer = Timer(timeInterval: delay,
                      target: callback,
                      selector: #selector(DebounceCallback.exec),
                      userInfo: ["arg": arg], repeats: false)
        if let t = timer { RunLoop.current.add(t, forMode: .default) }
    }
}
class DebounceCallback {
    let handler: (String)->Void
    init(_ handler: @escaping (String)->Void) { self.handler = handler }
    @objc func exec(t:Timer) {
        if let info = t.userInfo as? [String:String], let arg = info["arg"] { handler(arg) }
    }
}

// Test
final class Test {

    lazy var debouncedMyFunc: (String) -> Void = debounce(delay: 0.5, action: self.myFunc)

    init() {
        debouncedMyFunc("0")
        debouncedMyFunc("1")
        debouncedMyFunc("2")
        debouncedMyFunc("3")
        debouncedMyFunc("4")
        debouncedMyFunc("5")
        debouncedMyFunc("6")
        debouncedMyFunc("7")
        debouncedMyFunc("8")
        debouncedMyFunc("9")
    }
    
    func myFunc(text: String) {
        print("DEBOUNCED \(text)")
    }

}

Test()