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For better interoperability, Kotlin extends its static type function with moderate and flow elements. Moreover, it grants compile time among nullable and non-nullable types obtaining null safety. You now know how to use the Smart Cast in Kotlin! In the next chapter, we’ll discover how to handle exceptions.Kotlin also aids compilation platforms like JavaScript, Java Virtual Machine (JVM), and Native. If the attempt fails, the expression will be null. Safe Cast is the attempt to convert the type of a variable to another using the as keyword followed by the question mark ?. If the attempt fails, a ClassCastException will be thrown. Any is a function that is added as an extension to Iterable and Map interfaces, which take a higher-order function as param to predicate the condition and return Boolean as true, if any of the items in List, Set or Map confirms that condition, else return false. Unsafe Cast is the attempt to convert the type of a variable to another using the as keyword. Smart Cast is the automatic deduction of the type by the Kotlin compiler after a check with is.

In Kotlin, the instanceof keyword no longer exists and is replaced by is. 🎁 Already finished? The corrected version is right here. 🎓 How about a little exercise? This is where you can find it. Theory is good, but practice is even better! We’ve prepared a small interactive exercise at the end of the chapter so that you can apply all this new knowledge. Rather efficient, if I do say so myself! Practice Makes Perfect! Print(message) Result of the second approach: the Kotlin compiler assigns a null value to the variable val anyObject: Any = "Hello, Kotlin students!" It will allow us to perform a safe cast thanks to the keyword as followed by a question mark ? in order to explicitly tell the Kotlin compiler that, if the conversion fails, it will have to assign a null value to our variable. The second approach is more Kotlin-friendly. A Smart Conversion? private fun getDefaultSize(anyObject: Any): Int Result of the first approach: an error message is triggered

I’m getting there! Let’s write the same method right away, but in Kotlin. any ( predicate: (T) -> Boolean): Boolean Returns true if at least one element matches the given predicate.

(), listOf(), listOf() Lets see the example.