/* js/src/d2 /* js/src/d2/area /* js/src/d2/area/shoelace.js
function shoelace(edges) {

			var area = 0;

			var _iteratorNormalCompletion = true;
			var _didIteratorError = false;
			var _iteratorError = undefined;

			try {
				for (var _iterator = edges[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
					var _step$value = _slicedToArray(_step.value, 2);

					var u = _step$value[0];
					var v = _step$value[1];
					area += vcross2(u, v);
				}
			} catch (err) {
				_didIteratorError = true;
				_iteratorError = err;
			} finally {
				try {
					if (!_iteratorNormalCompletion && _iterator["return"]) {
						_iterator["return"]();
					}
				} finally {
					if (_didIteratorError) {
						throw _iteratorError;
					}
				}
			}

			return Math.abs(area) / 2;
		}