Null object: Difference between revisions
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For more detail on K's concept of typed nulls, see http://code.kx.com/wiki/Reference/Datatypes#Primitive_Types
=={{header|Kotlin}}==
Kotlin distinguishes between non-nullable types and nullable types. The latter are distinguished from the former by a '?' suffix. Only nullable types have a 'null' value indicating that they don't currently refer to an object of their non-nullable equivalent.
In addition, Kotlin has a Nothing type which has no instances and is a sub-type of every other type. There is also a nullable Nothing? type whose only value is 'null' and so, technically, this is the type of 'null' itself.
Here are some examples:
<lang scala>// version 1.1.0
fun main(args: Array<String>) {
val i: Int = 3 // non-nullable Int type - can't be assigned null
println(i)
val j: Int? = null // nullable Int type - can be assigned null
println(j)
println(null is Nothing?) // test that null is indeed of type Nothing?
}</lang>
{{out}}
<pre>
3
null
true
</pre>
=={{header|Lasso}}==
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