Null object: Difference between revisions
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Confusingly, there is also <code>NSNull</code>, a singleton class with one value, <code>[NSNull null]</code>, used as a dummy object to represent the lack of a useful object. This is needed in collections like arrays and dictionaries, etc., because they do not allow <code>nil</code> elements, so if you want to represent some "empty" slots in the array you would use this.
=={{header|Objeck}}==
In Objeck, "Nil" is a value of every reference type.
<lang Objeck>
# here "object" is a reference
if(object = Nil) {
"object is null"->PrintLine();
}
</lang>
=={{header|OCaml}}==
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