package com.example.project.functions
// Higher-Order Function
fun <T> List<T>.customFilter(predicate: (T) -> Boolean): List<T> {
val result = ArrayList<T>()
for (item in this) {
if (predicate(item)) {
result.add(item)
}
}
return result
}
// Extension Function
fun String.removeSpaces(): String {
return this.replace(" ", "")
}
// Inline Function
inline fun <T> lock(lock: Any, body: () -> T): T {
// simulated lock
return body()
}
// Function with default args
fun join(
elements: List<String>,
separator: String = ", ",
prefix: String = "",
postfix: String = ""
): String {
return prefix + elements.joinToString(separator) + postfix
}
// Single Expression Function
fun double(x: Int): Int = x * 2
class Calculator {
// Operator overloading
operator fun plus(other: Calculator): Calculator = Calculator()
// Infix function
infix fun add(x: Int): Int {
return x + 10
}
}
fun usage() {
val list = listOf(1, 2, 3)
val filtered = list.customFilter { it > 1 }
val text = "Hello World"
println(text.removeSpaces())
val calc = Calculator()
val res = calc add 5
lock(calc) {
println("Inside lock")
}
}
