// retoor <retoor@molodetz.nl>
import "html" for Document
var doc = Document.parse("<div data-id='123' data-name='test' data-value='hello'>Content</div>")
var div = doc.querySelector("div")
var dataset = div.dataset
System.print(dataset["id"]) // expect: 123
System.print(dataset["name"]) // expect: test
System.print(dataset["value"]) // expect: hello
var noData = Document.parse("<span>No data</span>")
var span = noData.querySelector("span")
var emptyDataset = span.dataset
System.print(emptyDataset.count) // expect: 0
var partial = Document.parse("<p data-single='only'>Text</p>")
var p = partial.querySelector("p")
System.print(p.dataset["single"]) // expect: only
System.print(p.dataset.count) // expect: 1