I find that a lot of times I have a nullable objec...

# announcements

[eygraber]

I find that a lot of times I have a nullable object, and it sits in the middle of a call chain, and I don't want the whole chain to become nullable after it, and I don't want to use ?: because I have a sensible default that I could plug in. Could anything go wrong with using something like the following?

fun <T: Any?> T?.or(other: T): T {
  return if(this == null) {
    other
  }
  else {
    this
  }
}

[gjesse]

seems legit, i would clean it up a bit though:

fun <T: Any?> T?.or(other: T) = this ?: other

[gjesse]

i would also consider naming it orDefault(..) because or implies some boolean logic

[mg6maciej]

LGTM, but I think you don't need ? in <T : Any>.

[eygraber]

Thanks!

@mg6maciej I always get confused as to the difference between <T : Any> and <T : Any?>

[mg6maciej]

If you specify T as Any?, you allow it to be null, so argument to your function can be null.

[mg6maciej]

It also makes ? in T?.or redundant.

[mg6maciej]

If you specify the function as:

fun <T: Any> T?.or(other: T) = this ?: other

it will not accept null as argument, but it will as receiver.

[eygraber]

@mg6maciej is there any way to only accept nullable receivers? What you have above allows me to call or on non-nullable objects.

[stepango]

why not just use ?: ?