javascript - Fat arrow function and how a fat arrow function works -


this question has answer here:

i saw question in quiz, how fat arrowed question works? there difference in following code, if if yes why, if no why?:

    var abc = function() {         return {           log : function() {             console.log(this.val);           }         };     }      var def = function(){         return{           log : () => {             console.log(this.val);           }         };     }

a fat arrow function automatically binds this. avoid code have save this in other variable that... such in nested callback hell. more terse.


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