Rest Parameters

Added in ES 2015
The Rest Parameter syntax allows a function to accept any number of arguments as an array.
This syntax is represented by three dots (...) which is the same syntax as the spread operator.

function MyFunction(...myArgs) { 
   return myArgs.reduce((previous, current) => { 
      return previous + current; 
   }); 
} 

console.log myFunction(1,2,3,4)   // 10 

console.log myFunction(4,5,6,7)   // 22