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Programming Fundamentals/Nothing Data Type
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Overview
A nothing data type is a feature of some programming languages which allow the setting of a special value to indicate a missing or uninitialized value rather than using the value 0 (zero).Wikipedia: Nullable type
Discussion
Most programming languages support the use of a reserved word or words to represent missing, uninitialized, or invalid values.
LanguageReserved WordMeaningC++nullno valueC#nullno valueJavanullno valueJavaScriptnullno valueJavaScriptNaNNot a NumberPythonNoneno valueSwiftnilno value
Key Terms
NaN
Reserved word used to indicate a non-numeric value in a numeric variable.
Null
Reserved word used to represent a missing value or invalid value.
References