lightbox-data.js

// For each image in the dataset, output this object:
// { src: "picture-3.jpg", caption: "Lorem Ipsum Dolor 2<br>Ut enim ad minim veniam, quis nostrud exercitation ullamco<br>2017" }

const data = [
	{
		"title": "Lorem Ipsum Dolor 1",
		"description": "Ut enim ad minim veniam, quis nostrud exercitation ullamco.",
		"year": "2018",
		"images": [
			"picture-1.jpg",
			"picture-2.jpg"
		]
	},
	{
		"title": "Lorem Ipsum Dolor 2",
		"description": "Ut enim ad minim veniam, quis nostrud exercitation ullamco",
		"year": "2017",
		"images": ["picture-3.jpg"]
	},
]

// reduce takes two arguments. a function and an initial value. Initialise with empty array
// acc is accumulated value, curr is current item
const works = data.reduce((acc, curr) => {
	// For each image, build an 'image object'
	// I would use map, but that will return an array, so this is how you can get around using that flatten
	curr.images.forEach(image => {
		acc.push({
		  src: image,
		  caption: `${curr.title}<br>${curr.description}<br>${curr.year}`
		});
	});
	
	return acc;
}, []);

// don't need flattened works anymore!

aha.. thanks so much! :)