Anyone else thinks it would be nice to have a `Str...

# stdlib

[edrd]

Anyone else thinks it would be nice to have a String.prepend(value: String) in the stdlib? I need it quite often and .let { "prefix$it" } doesn't express intent so well.

[Shawn]

what’s wrong with something like this?

val myString = "prefix" + getStringToPrependTo()

[edrd]

Nothing wrong, it's just that it doesn't express intent so well. For example, in my opinion this:

fun String.normalizeHttpsUrl() =
  if (string.startsWith("https://")) this
  else this.prepend("https://")

is more human-readable than this:

fun String.normalizeHttpsUrl() =
  if (string.startsWith("https://")) this
  else "https://$this"

[edrd]

(ignore the fact this is a very simple and dumb example)

[mbonnin]

I'd do "https://${this.removePrefix("https://")}" for this specific example

[Guilherme Cordeiro]

fun String.normalizeHttpsUrl() =
  if (string.startsWith("https://")) this
  else "https://".append(this)

Just an opinion, but this reads nice too, as the parts are in the order they'll appear on the final string

[edrd]

Thanks for your inputs. I think a better example would be when the string is nullable and a value should be prepended only when it's not null.

val result: String? = someNullableString
  ?.doSomeTransformation()
  ?.prepend("something")

IMO it reads better than

val result: String? = someNullableString
  ?.doSomeTransformation()
  ?.let { "something$it" }

[edrd]

Because for appending values it's possible without .let by using .plus