How to use @hpcc-js/composite - 2 common examples

describe(`${item.prototype.constructor.name}`, () => {
                    if (item.prototype instanceof Class) {
                        classDef("composite", item);
                    }
                    if (item.prototype instanceof HTMLWidget || item.prototype instanceof SVGWidget) {
                        switch (item.prototype.constructor) {
                            case MultiChart:
                                render(new MultiChart()
                                    .columns(data.Pivot.subjects.columns)
                                    .data(data.Pivot.subjects.data)
                                    .chartType("COLUMN")
                                );
                            case Dermatology:
                            case MegaChart:
                            case MultiChartPanel:
                                break;
                            default:
                                it("Missing test", () => {
                                    expect(false).to.be.true;
                                });
                        }
                    }
                });
            }

this.loadWidgets(["../composite/MegaChart", widgetPath], function (megaChart, widgets) {
            const chart = new widgets[1]();
            megaChart
                .chartType_default(MultiChart.prototype._allChartTypesByClass[chart.classID()].id)
                .chart(chart)
                ;
            if (callback) {
                callback(megaChart, chart, widgets);
            }
        });
    }