Kotlin

Kotlin

Javaを使用しない

val string = "Hello World"
var varString = "Hello World"

val string: String? = null
string?.length
string!!.length

lateinit var string: String

val string: String by lazy { 
	"string"
}

val string = "Hello World".run { 
                
}
val string = "Hello World".apply {
                
}
val string = "Hello World".let {
                
}
val string = "Hello World".also {
                
}
with(string){
                
}

val numbers = listOf("one", "two", "three", "four")
val numbers = mutableListOf(1, 2, 3, 4)

fun String.addAge(age: Int): String {
	return "$this $age"
}

fun print(body: (String, String) -> String) {
	println(body("A", "B"))
}

fun test() {
	print({ a, b ->
		"$a $b"
	})
}