send errors from event handlers to output editor

0004-on.update

@@ -8,5 +8,5 @@ on.update = function(dt)
 	elseif Current_pane.output_editor_state.scrollbar_drag then
 		adjust_scrollbar(Current_pane.output_editor_state, App.mouse_y())
 	end
-	if car.update then car.update(dt) end
+	if car.update then call_protected(car.update, dt) end
 end

0012-on.draw

@@ -3,7 +3,7 @@ on.draw = function()
 	love.graphics.setBackgroundColor(Background_color.r, Background_color.g, Background_color.b)
 	draw_canvas()
 	App.color(Foreground_color)
-	if car.draw then car.draw() end  -- off canvas
+	if car.draw then call_protected(car.draw) end  -- off canvas
 	if Show_code then
 		draw_editor_border()
 		edit.draw(Current_pane.editor_state, --[[implicitly use Foreground_color]] nil, --[[hide_cursor]] nil, --[[show_line_numbers]] true)

0013-on.keychord_press

@@ -12,7 +12,11 @@ on.keychord_press = function(chord, key)
 		end
 	else
 		-- editors hidden
-		if car.keychord_press then car.keychord_press(chord, key) end
-		if car.keypressed then car.keypressed(key) end
+		if car.keychord_press then
+			call_protected(car.keychord_press, chord, key)
+		end
+		if car.keypressed then
+			call_protected(car.keypressed, key)
+		end
 	end
 end

0014-on.text_input

@@ -5,7 +5,11 @@ on.text_input = function(t)
 		end
 	else
 		-- editors hidden
-		if car.text_input then car.text_input(t) end
-		if car.textinput then car.textinput(t) end
+		if car.text_input then
+			call_protected(car.text_input, t)
+		end
+		if car.textinput then
+			call_protected(car.textinput, t)
+		end
 	end
 end

0015-on.key_release

@@ -5,7 +5,11 @@ on.key_release = function(key, scancode)
 		end
 	else
 		-- editors hidden
-		if car.key_release then car.key_release(key, scancode) end
-		if car.keyreleased then car.keyreleased(key, scancode) end
+		if car.key_release then
+			call_protected(car.key_release, key, scancode)
+		end
+		if car.keyreleased then
+			call_protected(car.keyreleased, key, scancode)
+		end
 	end
 end

0017-on.mouse_release

@@ -16,7 +16,11 @@ on.mouse_release = function(x,y, mouse_button)
 		end
 	else
 		-- editors hidden
-		if car.mouse_release then car.mouse_release(x,y, mouse_button) end
-		if car.mousereleased then car.mousereleased(x,y, mouse_button) end
+		if car.mouse_release then
+			call_protected(car.mouse_release, x,y, mouse_button)
+		end
+		if car.mousereleased then
+			call_protected(car.mousereleased, x,y, mouse_button)
+		end
 	end
 end

0051-run_button

@@ -8,17 +8,17 @@ run_button = function(x)
 		end,
 		onpress1 = function()
 			-- ## run: initialize
+			clear_handlers()
 			local buf = table.concat(map(Current_pane.editor_state.lines, function(line) return line.data end), '\n')
 			Current_pane.canvas = love.graphics.newCanvas()
 			love.graphics.setCanvas(Current_pane.canvas)
 			love.graphics.push('all')
 			love.graphics.setBackgroundColor(1,1,1)
-			Current_pane.output_editor_state.lines = {}
-			Text.redraw_all(Current_pane.output_editor_state)
+			edit.clear(Current_pane.output_editor_state)
 			local real_print = print
 			print = print_to_output
 			-- ## run
-			local status, result = live.eval(buf)
+			local status, result = live.eval(buf, 'editor')
 			-- ## run: save some stuff, clean up the rest
 			print = real_print
 			if result then

0101-on.mouse_wheel_move

@@ -3,7 +3,11 @@ on.mouse_wheel_move = function(dx,dy)
 		-- nothing yet
 	else
 		-- editors hidden
-		if car.mouse_wheel_move then car.mouse_wheel_move(dx,dy) end
-		if car.wheelmoved then car.wheelmoved(dx,dy) end
+		if car.mouse_wheel_move then
+			call_protected(car.mouse_wheel_move, dx,dy)
+		end
+		if car.wheelmoved then
+			call_protected(car.wheelmoved, dx,dy)
+		end
 	end
 end

0102-send_errors_to_output

@@ -0,0 +1,7 @@
+send_errors_to_output = function(err)
+	local callstack = debug.traceback('', 3)
+	local error_with_callstack = cleaned_up_frame(tostring(err))..'\n'..cleaned_up_callstack(callstack)
+	Text.insert_text(Current_pane.output_editor_state, error_with_callstack)
+	Text.redraw_all(Current_pane.output_editor_state)
+	clear_handlers()
+end

0104-call_protected

@@ -0,0 +1,8 @@
+call_protected = function(f, ...)
+	local args = {...}
+	xpcall(
+		function()
+			f(unpack(args))
+		end,
+		send_errors_to_output)
+end

0105-clear_handlers

@@ -0,0 +1,5 @@
+clear_handlers = function()
+	for k in pairs(car) do
+		car[k] = nil
+	end
+end

edit.lua

@@ -394,6 +394,13 @@ function Text.insert_text(State, d)
   end
 end
 
+function edit.clear(State)
+  State.lines = {{data=''}}
+  Text.redraw_all(State)
+  State.cursor1 = {line=1, pos=1}
+  State.screen_top1 = {line=1, pos=1}
+end
+
 function edit.key_release(State, key, scancode)
 end
 

reference.md

@@ -196,6 +196,8 @@ early warning if you break something.
   `x=right`. Wraps long lines at word boundaries where possible, or in the
   middle of words (no hyphenation yet) when it must.
 
+* `edit.clear_state(state)` -- empties the editor of any text it may contain.
+
 * `state.lines = load_array(lines)` -- loads the editor state with the array
   of `lines`