Hello! Does stdlib contains multiplatform String.format(string, args) function?

Note that string interpolation works on all platforms.

Yes. I need for runtime provided string with args.

Out of curiosity, what's the use case?

In db there are string templates. And there is context info that flat mapped to array of values.

you could build your own mini-formatter like

fun String.format(vararg args: Any?): String = buildString {
    var index = 0
    var position = 0
    while (position < this@format.length) {
        val next = this@format.indexOf('%', startIndex = position)
        if (next < 0) break
        append(this@format.substring(position, next))
        when (val c = this@format.getOrNull(next + 1)) {
            '%' -> append('%')
            's' -> append(args[index++])
            'd' -> append((args[index++] as Number).toInt())
            'l' -> append((args[index++] as Number).toLong())
            'e', 'f', 'g' -> append((args[index++] as Number).toDouble())
            else -> throw IllegalArgumentException(if (c == null) "%" else "%$c")
        }
        position = next + 2
    }
    append(this@format.substring(position))
}

but supporting the full set of features that the Java string formatter has (which Kotlin/JVM simply delegates to) is challenging

Yes. I've done someting like this. Just wanted to be sure that I'm not doing things stdlib already have.