Javascript closure and scope riddle -


i'v heard question, , i'm unsure how solve it.

the requirement is: implement function from preform on following scenario:

var x = from(3); console.log(x()); //outputs 3 console.log(x()); //outputs 4 //todo: implement from()

i tried like:

function from(val) {   var counter = val;   return function(){     return counter+=1;   } }

but first time run it, increments value, that's no go.

var x = from(3);  function from(startvalue) {    var counter = startvalue;    return function() {      return counter++;    } }  console.log(x()); //outputs 3 console.log(x()); //outputs 4

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