The Kotlin Standard Library

fun main() {
    val fruits = listOf("apple", "banana", "cherry")
    println(fruits.joinToString(", "))
    println("ab".repeat(3))
}

fun main() {
    val value = 150
    println("Clamped: ${value.coerceIn(0, 100)}")
    println("At most 50: ${value.coerceAtMost(50)}")
}

fun main() {
    val numbers = listOf(5, 3, 8, 1, 9)
    println("Sorted: ${numbers.sorted()}")
    println("Max: ${numbers.max()}")
    println("Chunked: ${numbers.chunked(2)}")
}

fun main() {
    // kotlin-stdlib alone is enough for everything in this example
    val date = "2024-01-15"
    val parts = date.split("-")
    println("Year: ${parts[0]}, Month: ${parts[1]}, Day: ${parts[2]}")
}

1. Reimplementing common utilities, like finding the max of two numbers or joining a list into text, that the standard library already provides.
2. Assuming every convenient function (like coroutines or serialization) is part of the standard library, when many are separate kotlinx libraries requiring their own dependency.
3. Not exploring collection, string, and scope function utilities before writing manual loops for tasks they already solve concisely.

• The Kotlin standard library (kotlin-stdlib) ships with the compiler and provides collections, string utilities, scope functions, and more, with no extra dependency needed.
• Libraries like kotlinx.coroutines, kotlinx.serialization, and kotlinx.datetime are separate from the standard library and must be added explicitly.
• Common standard library helpers include .joinToString(), .coerceIn(), .repeat(), and the scope functions covered earlier.
• Checking the standard library first often avoids writing verbose manual logic for common tasks.