Notions fondamentales des chaînes : littéraux, séquences d’échappement et longueur

val greeting = "Hello, Kotlin!"
val empty = ""
val withSpaces = "  trimmed  "

println("Line 1\nLine 2")
println("Col1\tCol2")
println("She said \"hello\".")
println("Path: C:\\Users")

val name = "Kotlin"
println(name.length)      // 6
println("".length)        // 0
println("  hi  ".length) // 6 (spaces count)

val s = "Hello"
println(s[0])         // H
println(s[4])         // o
println(s.first())    // H
println(s.last())     // o

println("".isEmpty())         // true
println("  ".isEmpty())       // false
println("  ".isBlank())       // true
println("hi".isBlank())       // false

val a = "hello"
val b = "hello"
println(a == b)           // true (content)
println(a.equals(b, ignoreCase = true)) // true

val text = "Hello, Kotlin!"
println(text.substring(7))      // Kotlin!
println(text.substring(0, 5))   // Hello

val s = "Hello, Kotlin!"
println(s.indexOf("Kotlin"))   // 7
println(s.contains("Hello"))   // true
println("Kotlin" in s)        // true (in operator)

val s = "hello kotlin"
println(s.uppercase())          // HELLO KOTLIN
println(s.lowercase())          // hello kotlin
println(s.replaceFirstChar { it.uppercase() })

val s = "hello"
val upper = s.uppercase()  // new string
println(s)     // still "hello"
println(upper) // "HELLO"