Adding Char.repeat to stdlib

Libraries
1

We have CharSequence.repeat which produces a String. I would like Char.repeat which would also produce a String. Then you can do e.g. '*'.repeat(5) and get a String.

Can this be added?

2

What stops you from writing "*".repeat(5) and getting the same result?

3

If you want something to add to stdlib, you have to give a use case for that. Especially when it could be don with one-liner extension.

1 Like
4

Sometimes I’m working with Chars and not Strings. For example, this leetcode problem Loading...

Assuming we had Char.repeat it would look like

fun customSortString(order: String, string: String): String {
    val occurrences = string.groupingBy { it }.eachCountTo(HashMap())
    return buildString(string.length) {
        for (char in order) {
            occurrences[char]?.also {
                append(char.repeat(it))
                occurrences -= char
            }
        }
        for ((char, times) in occurrences) {
            append(char.repeat(times))
        }
    }
}

This is a trivial example so even without Char.repeat it’s fine:

fun customSortString(order: String, string: String): String {
    val occurrences = string.groupingBy { it }.eachCountTo(HashMap())
    return buildString(string.length) {
        for (char in order) {
            occurrences[char]?.also {
                repeat(it) { append(char) }
                occurrences -= char
            }
        }
        for ((char, times) in occurrences) {
            repeat(times) { append(char) }
        }
    }
}
5

The use case is the exact same as for CharSequence.repeat except for when you’re dealing with Chars. A String is a sequence of chars so being able to repeat a char and get a String makes sense to me. I added a trivial example in another comment in this thread. And sure, I could, and have implemented it myself, but much like CharSequence.repeat I think it’s a standard utility that others would find helpful.