simple-cache.js

// Create an instance of our cache and set some keys. Notice that the [new] operator
// is optional since the SimpleCache (and revealing module pattern) doesn't use
// prototypical inheritance. And, we can use method-chaining to set the cache keys.
var cache = SimpleCache()
	.set( "foo", "Bar" )
	.set( "hello", "world" )
	.set( "beep", "boop" )
;

console.log( cache.has( "beep" ) );


// ---------------------------------------------------------- //
// ---------------------------------------------------------- //


// I provide a super simple cache container.
function SimpleCache() {

	// Create an object without a prototype so that we don't run into any cache-key
	// conflicts with native Object.prototype properties.
	var cache = Object.create( null );

	// Reveal the public API.
	return({
		get: get,
		has: has,
		remove: remove,
		set: set
	});


	// ---
	// PUBLIC METHODS.
	// ---


	// I get the value cached at the given key; or, undefined.
	function get( key ) {

		return( cache[ key ] );

	}


	// I check to see if the given key has a cached value.
	function has( key ) {

		return( key in cache );

	}


	// I remove the given key (and associated value) from the cache.
	// --
	// NOTE: Returns [this] for method chaining.
	function remove( key ) {

		delete( cache[ key ] );

		// CAUTION: In this context, [this] does not refer to the SimpleCache instance;
		// rather, it refers to the public API that was "revealed". As such, method
		// chaining can only work in conjunction with "public" methods.
		return( this );

	}


	// I cache the given value at the given key.
	// --
	// NOTE: Returns [this] for method chaining.
	function set( key, value ) {

		cache[ key ] = value;

		// CAUTION: In this context, [this] does not refer to the SimpleCache instance;
		// rather, it refers to the public API that was "revealed". As such, method
		// chaining can only work in conjunction with "public" methods.
		return( this );

	}

}