kotlin-stdlib/kotlin.sequences/joinTo

joinTo

fun <T, A : Appendable> Sequence<T>.joinTo(buffer: A, separator: CharSequence = ", ", prefix: CharSequence = "", postfix: CharSequence = "", limit: Int = -1, truncated: CharSequence = "...", transform: (T) -> CharSequence? = null): A(source)

Appends the string from all the elements separated using separator and using the given prefix and postfix if supplied.

If the collection could be huge, you can specify a non-negative value of limit, in which case only the first limit elements will be appended, followed by the truncated string (which defaults to "...").

The operation is terminal.

Since Kotlin

1.0

Samples

import kotlin.test.*

fun main() { 
   //sampleStart 
   val sb = StringBuilder("An existing string and a list: ")
val numbers = listOf(1, 2, 3)
println(numbers.joinTo(sb, prefix = "[", postfix = "]").toString()) // An existing string and a list: [1, 2, 3]

val lotOfNumbers: Iterable<Int> = 1..100
val firstNumbers = StringBuilder("First five numbers: ")
println(lotOfNumbers.joinTo(firstNumbers, limit = 5).toString()) // First five numbers: 1, 2, 3, 4, 5, ... 
   //sampleEnd
}