/* import jsdom fn get_2dcontext(canvas jsdom.IElement) ?jsdom.CanvasRenderingContext2D { if canvas is jsdom.HTMLCanvasElement { c := canvas.get_context('2d') match c { jsdom.CanvasRenderingContext2D { return c } else { return error('cannot fetch 2d context') } } } else { return error('canvas is not an HTMLCanvasElement') } } fn draw_line(context jsdom.CanvasRenderingContext2D, x1 int, y1 int, x2 int, y2 int) { context.begin_path() context.set_stroke_style('black') context.set_line_width(1) context.move_to(x1, y1) context.line_to(x2, y2) context.stroke() context.close_path() } struct DrawState { mut: drawing bool x int y int } fn main() { document := jsdom.document elem := document.get_element_by_id('myButton') ? elemc := document.get_element_by_id('myCanvas') or { panic('no canvas') } canv := jsdom.get_html_canvas_element(elemc) or { panic('expected canvas') } context := canv.get_context_2d() mut state := DrawState{} canv.add_event_listener('mousedown', fn [mut state] (_ jsdom.IEventTarget, event jsdom.IEvent) { state.drawing = true if event is jsdom.MouseEvent { state.x = event.offset_x() state.y = event.offset_y() } }) canv.add_event_listener('mousemove', fn [context, mut state] (_ jsdom.IEventTarget, event jsdom.IEvent) { if state.drawing { if event is jsdom.MouseEvent { draw_line(context, state.x, state.y, event.offset_x(), event.offset_y()) state.x = event.offset_x() state.y = event.offset_y() } } }) jsdom.window.add_event_listener('mouseup', fn [context, mut state] (_ jsdom.IEventTarget, event jsdom.IEvent) { if state.drawing { if event is jsdom.MouseEvent { draw_line(context, state.x, state.y, event.offset_x(), event.offset_y()) } state.x = 0 state.y = 0 state.drawing = false } }) elem.add_event_listener('click', fn [context, canv] (_ jsdom.IEventTarget, _ jsdom.IEvent) { context.clear_rect(0, 0, canv.width(), canv.height()) }) } */ fn main() { panic('jsdom is being refactored; This example will be available soon') }