生成并使用自然數(shù)
val naturalNumbers = generateSequence(0){ it +1 }
naturalNumbers.takeWhile{ it <= 100 }.sum() //5050
支持with操作,和Js的with差不多
fun aToz() = with(StringBuilder()){ //返回表達(dá)式值
for ( c in 'a'..'z'){
append(c)
}
toString()
// this@OuterClass.toString() 調(diào)用外部的toString
}
apply函數(shù)
fun aToz1() = StringBuilder().apply{ //返回對(duì)象
for ( c in 'a'..'z'){
append(c)
}
}.toString()
==
fun aToz2() = buildString{ // buildString 系統(tǒng)內(nèi)建函數(shù)
for ( c in 'a'..'z'){
append(c)
}
}
