Null and undefined are obviously wrong ways to use them

Example:

let ResultIsNumber17 = +(null + undefined);
 // Operator '+' cannot be applied to types 'undefined' and 'undefined'.
 ​
let ResultIsNumber18 = +(null + null);
 // Operator '+' cannot be applied to types 'null' and 'null'.
 ​
let  ResultIsNumber19 = +(undefined + undefined);
 // Operator '+' cannot be applied to types 'undefined' and 'undefined'.
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Similarly, null and undefined will cause an error when used as objects with methods.

Example:

null.toBAZ();

undefined.toBAZ();
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