let displayColors = function(message ...colors){};

Looking at this variable function above, you can clearly see the usagave of ... which is called a REST VARIABLE.

I am learning typescript right now, and the way i understand this feature in typescript ECMAScript ES6 is that this can help you create an array. this is very helpful if you want to pass down an array into a function.

this is an example of using Restp operators:

//the spread operator takes an array and splits it into individual elements
//this is an example of the REST operator

let displayColors = function(message ...colors){
    console.log(message);
    console.log(colors); // shows the array properties
    console.log(arguments.length); // shows how many elements
    for(let i in colors){
        console.log(colors[i]);
    }
}
let message = "List of Colors";
let colorArray = ['orange','yellow','purple'];
displayColors(message, ...colorArray); // HERE IS THE DIFFERENCE BETWEEN REST AND SPREAD. YOU USE THE THREE DOTS WHEN YOU CALL THE FUNCTION

if you still need help, i learn about rest operators from this video:
REST = TO COMBAINE / SPREAD = SPLIT
https://www.youtube.com/watch?v=Fc6DPYx9aQU&index=14&list=PLC3y8-rFHvwhI0V5mE9Vu6Nm-nap8EcjV

... What Do The Three Dots Mean In Typescript - Rest Operator

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