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kotlinlang

If I have a function that requires not null variables, what is the best way to null check them before calling the function?

```if (foo != null) {
  myFunction(foo)
}```


The compiler will automatically smart-cast to the non-null type inside the if-expression.
<https://kotlinlang.org/docs/reference/typecasts.html#smart-casts>

If the function returns a result that you're using for assignment, you can also inline `if/else` with a default value or use non-null assertions, if you want an exception to be thrown if any of the variables are null.

If it is considered an error if null you could do:
```require(foo!=null) { "foo is required" }
myFunction(foo)```

<@U0XCN4RL2> can also make it nicer with
```requireNotNull(foo) { "..." }```

```if(foo == null) return
myFunction(foo)```
