What is the significance of this JavaScript code? -


what think doing looking see if object has been instantiated , exists within scope? why need use triple equal sign determine? 

   function viewmodel(parent) {              if (false === (this instanceof viewmodel)) {                 return new viewmodel(parent);             }      };

you don't need strict equality comparison there. instanceof yields true or false, entirely sufficient:

if (!(this instanceof viewmodel))

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