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Basic Usage of the 'in' and 'instanceOf' Operators

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Basic usage of the in and instanceOf operators.

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  1. function operators(){
  2. 	//Use of in Operator
  3. 	var o = {x: 1, y: 2};//Create object
  4. 	var haveX = "x" in o;//true
  5. 	var haveY = "y" in o;//true
  6. 	var haveZ = "z" in o;//false
  7. 	var haveMethod = "toString" in o;//true (inherited property)
  8. 	console.log(haveX, haveY, haveZ, haveMethod);
  9.  
  10. 	var a = [1, 2, 3];
  11. 	var check1 = a instanceof Array;//true
  12. 	var check2 = a instanceof Object;//true (array is an object)
  13. 	var check3 = a instanceof RegExp;//false
  14. 	console.log(check1, check2, check3);
  15.  
  16. 	var d = new Date();
  17. 	var check1 = d instanceof Date;//true
  18. 	var check2 = d instanceof Object;//true
  19. 	var check3 = d instanceof Number;//false
  20. 	console.log(check1, check2, check3);
  21. }

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