The value to check.
true if the value is considered defined; otherwise, false.
isDefined('hello'); // true
isDefined(123); // true
isDefined(false); // true
isDefined([1, 2]); // true
isDefined({ key: 'value' }); // true
isDefined([]); // true
isDefined({}); // true
isDefined(''); // true
isDefined(' '); // true
isDefined(null); // false
isDefined(undefined); // false
isDefined(NaN); // false
Checks whether a given value is "defined" in a broad and practical sense.
A value is considered defined if it does not meet any of the following:
null: explicitly nullundefined: not assignedNaN: Not-a-Number (only applies to numbers)