Little getter/setter for localStorage: store( 'name', 'barney' ); store( 'name' ) === 'barney'; store.delete( 'name' ); store.has( 'name' ) === false

store.js

// Get / setter for local storage
function store( key, value ){
	if( arguments.length > 1 ){
		localStorage.setItem( key, JSON.stringify( value ) )

		return value
	}
	// Simultaneous getting / setting is bad.
	// It is wasteful to continuously encode & then decompile JSON and never useful.
	else {
		const encoded = localStorage.getItem( key )

		// JSON parser fails violently when attempting to decode the string 'undefined'.
		// null, NaN and other primitives are fine.
		return encoded === 'undefined' ? undefined : JSON.parse( encoded )
	}
}

store.has    = key =>
// Really? Yes: localStorage.hasOwnProperty( 'length' ) === true, I kid you not
	Object.keys( localStorage ).some( thing => thing === key )

store.delete = key =>
	store.has( key ) && delete localStorage[ key ]

export default store