What is splat in CoffeeScript ?

CoffeeScript is a lightweight language that compiles into JavaScript. As compared to JavaScript, it provides simple and easy-to-learn syntax avoiding the complex syntax of JavaScript. CoffeeScript is influenced by languages such as JavaScript, YAML, Ruby, Python and has also influenced languages that are LiveScript, MoonScript.

Installation of CoffeeScript:

Install locally for a project

npm install --save-dev coffeescript

To globally install to execute the .coffee files anywhere

npm install --global coffeescript

Splat in CoffeeScript: In general, we can pass a fixed number of arguments to a function in CoffeeScript but what about if need to pass variable arguments to the functions.

Splats are the features provided by CoffeeScript that allows passing multiple arguments to functions. We can use splats in function just by placing three dots after the name of the argument.

Syntax:

functionName = ( argument1 , argument2...) -> 
    ...

Example: This example shows how to accept multiple arguments within a function using splats in CoffeeScript. We have defined a function named lang_type() using splat. We have called this function multiple times with different numbers of arguments passed. Since we have used splats in defining the function, each time we call the function it accepts the variable number of arguments.

Javascript

lang_type = (first, second, others...) ->
    FirstType = first
    SecondType = second
    OtherType  = others
    console.log "First Type: " +FirstType
    console.log "Second Type: " +SecondType
    console.log "Other types: " +OtherType

// Passing 2 arguments
console.log "############## Two types of
    languages ############"
lang_type "Monolithic", "Procedural"

// Passing 4 arguments
console.log "############## Four types of
    languages ############"
lang_type "Monolithic", "Procedural",
    "Functional", "Object Oriented"

On compiling, it gives the following result:

Javascript

(function () {
    var lang_type;

    lang_type = function (first, second, ...others) {
        var FirstType, OtherType, SecondType;
        FirstType = first;
        SecondType = second;
        OtherType = others;
        console.log("First Type: " + FirstType);
        console.log("Second Type: " + SecondType);
        return console.log("Other types: " + OtherType);
    };

    // Passing 2 arguments
    console.log("############## Two types of
        languages ############");

    lang_type("Monolithic", "Procedural");

    // Passing 4 arguments
    console.log("############## Four types of
        languages ############");

    lang_type("Monolithic", "Procedural",
        "Functional", "Object Oriented");

}).call(this);

Output :