Null-aware operators are used in almost every programming language to check whether the given variable value is Null . The keyword for Null in the programming language Dart is null. Null means a variable which has no values assign ever and the variable is initialized with nothing like.
Read moreWhat does after a variable mean in Dart?
Answer (1) A nullable type by adding a question mark (?) after the type name. For example, a variable _contacts? can contain a value, or it can be null. Answer (2) It is called “Null-aware operators”.
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