implement 'Run' button

Error flow is still klunky. We'll need to implement the output region
for that.

0012-on.draw

@@ -1,5 +1,7 @@
 on.draw = function()
 	Editor_state.button_handlers = {}
+	draw_canvas()
+	--if Canvas then return end
 	draw_editor_border()
 --	love.graphics.rectangle('line', 100-5-Line_number_padding,100-5, 300+Line_number_padding+10, 200+10, 5,5)
 	edit.draw(Editor_state)

0021-draw_menu

@@ -10,6 +10,18 @@ draw_menu = function()
 		end,
 		onpress1 = function()
 			print('run')
+			local buf = table.concat(map(Editor_state.lines, function(line) return line.data end), '\n')
+			Canvas = love.graphics.newCanvas()
+			love.graphics.setCanvas(Canvas)
+			love.graphics.push('all')
+			love.graphics.setBackgroundColor(1,1,1)
+			love.graphics.setColor(0,0,0)
+			local status, result = live.eval(buf)
+			if not status then
+				print(result)
+			end
+			love.graphics.pop()
+			love.graphics.setCanvas()
 		end,
 	})
 	-- settings button on right

0041-Canvas

@@ -0,0 +1 @@
+Canvas = nil

0042-draw_canvas

@@ -0,0 +1,7 @@
+draw_canvas = function()
+	if Canvas == nil then return end
+	love.graphics.setBlendMode('alpha', 'premultiplied')
+	love.graphics.setColor(1,1,1,1)
+	love.graphics.draw(Canvas, 0,0)
+	love.graphics.setBlendMode('alpha')
+end

0043-map

@@ -0,0 +1,7 @@
+map = function(arr, f)
+  local result = {}
+  for _, x in ipairs(arr) do
+    table.insert(result, f(x))
+  end
+  return result
+end