package com.example.project.edgecases
// 1. Destructuring Declarations
data class Point(val x: Int, val y: Int)
fun destructuring() {
val (x, y) = Point(1, 2)
}
// 2. Type Aliases
typealias NodeSet = Set<String>
typealias FileTable<K> = MutableMap<K, MutableList<File>>
fun processNodes(nodes: NodeSet) {}
// 3. Anonymous Objects (Object Expressions)
fun createListener() {
val listener = object : MouseAdapter() {
override fun mouseClicked(e: MouseEvent) {
println("Clicked")
}
}
}
// 4. Functional (SAM) Interfaces
fun interface IntPredicate {
fun accept(i: Int): Boolean
}
val isEven = IntPredicate { it % 2 == 0 }
// 5. Generic Constraints
fun <T> copyWhenGreater(list: List<T>, threshold: T): List<String>
where T : CharSequence,
T : Comparable<T> {
return list.filter { it > threshold }.map { it.toString() }
}
// 6. Contracts (Experimental)
import kotlin.contracts.*
fun require(condition: Boolean) {
contract {
returns() implies condition
}
if (!condition) throw IllegalArgumentException()
}
// 7. Value Classes (Inline Classes)
@JvmInline
value class Password(private val s: String)
// 8. Expect/Actual (Multiplatform) - purely syntax check if parser handles keywords
// expect fun format(str: String): String
// 9. Delegated Properties (Custom)
import kotlin.reflect.KProperty
class Delegate {
operator fun getValue(thisRef: Any?, property: KProperty<*>): String {
return "$thisRef, thank you for delegating '${property.name}' to me!"
}
}
class Example {
val p: String by Delegate()
}
// 10. Secondary Constructors
class Person {
var children: MutableList<Person> = mutableListOf()
constructor(parent: Person) {
parent.children.add(this)
}
}
// 11. Property in Constructor
class User(val name: String, var age: Int)
// 12. Enum Classes with methods
enum class ProtocolState {
WAITING {
override fun signal() = TALKING
},
TALKING {
override fun signal() = WAITING
};
abstract fun signal(): ProtocolState
}
