Traceur Compiling ES6 Spread Operator

• ES6 provides another useful operator called spread operator to work with Array.
• Spread operator is represented by 3 dots prefixed with a variable name.For example …fruitArray .
• In this demo, “We will learn to use spread operator by an example”.
• Spread operator is similar to an inline function which expand it self on the called position.
• The following code shows 2 students array mathStudents and lawStudents containing few student names.By using spread operator we are combing it to a single array.In the later part of the code a summation() method is declared which takes a spread array as input parameter and iterate over it and returns the total sum by adding each item present in the spread array.

  var mathStudents = ["Sandeep","Sangeeta","Surabhi"];
  var lawStudents = ["Sumanta","Rohan","Surendra"];
  var allStudents= ["John", ...mathStudents,"Jack",...lawStudents];
  console.log(allStudents);
  var numberArray= [12,21,32,40];
  var summation = function(...items){
    var sum = 0;
    items.forEach(function(item) {
      sum = sum+item;
    });
    return sum;
  };
  var result = summation(...numberArray);
  console.log(result);
  

• The output of the code can be found in the following embedded JSBIN link.

JS Bin