kotlin.collections.joinToString - Example

 

// 1, 2, 3, 4, 5, 6
println(numbers.joinToString())
// [1, 2, 3, 4, 5, 6]
println(numbers.joinToString(prefix = "[", postfix = "]"))
// <1•2•3•4•5•6>
println(numbers.joinToString(prefix = "<", postfix = ">", separator = "•")) 

val chars = charArrayOf('a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 
    'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q')
// A, B, C, D, E, ...!
println(chars.joinToString(limit = 5, truncated = "...!") { it.uppercaseChar()
.toString() }) 

Reference

https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/join-to-string.html