Currying In Js

curry.js

 function curry(fn) {
   //create sunt double function to check artiy of the calling function i.e fn
   return function() {
     //check the length of args and if its greater copy them and return a new function
     if (fn.length > arguments.length) {
       //copy logic
       var slice = Array.prototype.slice;
       var args = slice.apply(arguments)
       //new function with args copied
       return function() {
         return fn.apply(
           null, args.concat(slice.apply(arguments)));
       };
     }
     //else just pass the arguments back to the original
     return fn.apply(null, arguments);
   };
 }