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kotlinlang

just drawing a blank here: is the not a shortcut for `if (predicate(x)) f(x) else null`?

you could
```x.takeIf(::predicate)?.let(::f)```
if `x` is not null, but the way you wrote it with `if` is clearer

yeah, I had this and it's not nicer, so reverted.  But then I thought I missed something like a `Any?.runIf` . Seems I was mistaken

We are considering adding `runIf` function to stdlib
```fun &lt;T&gt; runIf(cond: Boolean, block: () -&gt; T): T? = if (cond) block() else null```
But this function requires new kind of contracts which allows to propagate smartcast info from condition to lambda body
```fun test(x: String?) {
    val y = runIf(x != null) {
        x.length // should be smartcast to String
    }
}```
And those new contracts will be possible to implement only in K2 compiler

nice. I have written and used an `.applyIf()` extension in several projects (even without smartcasting); I think I would get more use out of that than `runIf()` but it's almost equivalent

wouldn't it conform more to the naming convention in Kotlin, if the function was called `runIfOrNull` !?

There is no final decision yet about this function