@data @override @pure @fun @overrideFun
@in @out @some
@get @set @protectedGet @protectedSet

├── [ 1.8K]  Data.class
├── [ 1.1K]  KvMap$1.class
├── [  917]  KvMap$KvPair$Mutable$Of.class
├── [  505]  KvMap$KvPair$Mutable.class
├── [ 2.0K]  KvMap$KvPair$Of.class
├── [  667]  KvMap$KvPair.class
├── [ 2.5K]  KvMap$Mutable.class
├── [ 4.5K]  KvMap.class
├── [  447]  OperationNotSupportedException$Mutability.class
├── [ 1.1K]  OperationNotSupportedException.class
├── [ 1.6K]  RangeIE$IntRange.class
├── [ 1.6K]  RangeIE$LongRange.class
├── [  381]  RangeIE.class
├── [ 1.7K]  RangeMap$Mutable.class
├── [  990]  RangeMap$Ray$Shadow.class
├── [ 1.1K]  RangeMap$Ray$White.class
├── [ 1.1K]  RangeMap$Ray.class
├── [ 1.7K]  RangeMap.class
└── [  258]  RayRangeMap.class

sealed class SumTree {
  data class Group(val children: Iterable<SumTree>): SumTree()
  data class Tip(val n: Int): SumTree()
  interface Visitor<out R> {
    fun see(x: Tip):R fun see(g: Group):R }
  fun <R> rewriteBy(vis: Visitor<R>): R = when (this) { 
    is Tip -> vis.see(this)  
    is Group -> vis.see(this)
  }
}  

object Sumer : SumTree.Visitor<Int> {   
  override fun see(x: SumTree.Tip) = x.n
  override fun see(g: SumTree.Group) = g.children.sumBy { sum(it) }
  private fun sum(t: SumTree) = t.rewriteBy(this)
}

>>> SumTree.Group(listOf(1,2,3).map(SumTree::Tip).asIterable())
Group(children=[Tip(n=1), Tip(n=2), Tip(n=3)])
>>> SumTree.Group(listOf(1,2,3).map(SumTree::Tip).asIterable()).rewriteBy(Sumer)
6

@NamePrefixed(prefix = "Aa") public class A {}

循环 1:
        输入文件: {A}
        注释: [NamePrefixed]
        最后一个循环: false
处理程序Processor与[NamePrefixed]匹配并返回true。
注: Prefix: Aa from [NamePrefixed]
警告: Name A does not started with Aa
循环 2:
        输入文件: {}
        注释: []
        最后一个循环: true
1 个警告

(A∪B) = {x | x∈A ∨ x∈B}
(Int∪String) = {1,2,3,"A","B","C",...}

try { scanUserInput(); }
catch (EOFException | ReadError | ParserError e) { e.printStackTrace(); }

(A∩B) = {x | x∈A ∧ x∈B}
(String∩Object) = {"a", "str", ...}
(Exception∩RuntimeException) = RuntimeException

val rm = RangeMap<Int, String>()
rm[0 until 1] = "0"
rm[1 until 4] = "123"
rm[4 until 6] = "45"

assert (0 in rm)
assert (3 in rm)
assert (rm.containsEdge(0))
assert (6 !in rm)
assert (rm[0] == "0")
assert (rm[3] == "123")
assert (rm[5] == "45")
assert (rm.containsShadow(5))