Kotlin null check for multiple nullable var's

Language Design
13

I see a few other options not yet discussed in case it helps:

  1. Use an intermediary function to copy the property values thereby making smart cast possible:

    class Person(var name: String? = null, var age: Int? = null) {
    fun test() = test(name, age)
    private fun test(name: String?, age: Int?) {
        if (name != null && age != null)
            doSth(name, age) //smart cast possible
    }

    fun doSth(someValue: String, someValue2: Int) {

    }
}

  2. Use an anonymous function (same idea as #1):

    class Person(var name: String? = null, var age: Int? = null) {
    fun test() = (fun(name: String?, age: Int?) {
        if (name != null && age != null)
            doSth(name, age) //smart cast possible
    })(name, age)

    fun doSth(someValue: String, someValue2: Int) {

    }
}

  3. Use default arguments to copy the property values:

    class Person(var name: String? = null, var age: Int? = null) {
    fun test(name: String? = this.name, age: Int? = this.age) {
        if (name != null && age != null)
            doSth(name, age) //smart cast possible
    }

    fun doSth(someValue: String, someValue2: Int) {

    }
}
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