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main.lua

Slab = require 'Slab'  -- idiomatic GUI: https://github.com/flamendless/Slab

-- default love.run from https://love2d.org/wiki/love.run with various callbacks wrapped in xpcall()
function love.run()
  if love.load then love.load(love.arg.parseGameArguments(arg), arg) end

  -- We don't want the first frame's dt to include time taken by love.load.
  if love.timer then love.timer.step() end

  local dt = 0

  -- Main loop time.
  return function()
    -- Process events.
    if love.event then
      love.event.pump()
      for name, a,b,c,d,e,f in love.event.poll() do
        if name == "quit" then
          if not love.quit or not love.quit() then
            return a or 0
          end
        end
        xpcall(function() love.handlers[name](a,b,c,d,e,f) end, handle_error)
      end
    end

    -- Update dt, as we'll be passing it to update
    if love.timer then dt = love.timer.step() end

    -- Call update and draw
    if love.update then xpcall(function() love.update(dt) end, handle_error) end -- will pass 0 if love.timer is disabled

    if love.graphics and love.graphics.isActive() then
      love.graphics.origin()
      love.graphics.clear(love.graphics.getBackgroundColor())

      if love.draw then xpcall(love.draw, handle_error) end

      love.graphics.present()
    end

    if love.timer then love.timer.sleep(0.001) end
  end
end

function love.load()
  love.keyboard.setKeyRepeat(true)
  love.keyboard.setTextInput(true)

  Slab.Initialize()
  InputText = 'function love.draw() error("aaa") end'
  Error_message = nil
  LineHeight = Slab.GetTextHeight()
  W, H = love.window.getMode()

  -- save all MiniIDE handlers
  MiniIDE_handlers = {}
  for name,def in pairs(love.handlers) do
    MiniIDE_handlers[name] = def
  end
  MiniIDE_handlers.update = love.update
  MiniIDE_handlers.draw = love.draw
end

function handle_error(err)
  Error_message = debug.traceback('Error: ' .. tostring(err), --[[stack frame]]2):gsub('\n[^\n]+$', '')
  -- restore all MiniIDE handlers
  for name,def in pairs(MiniIDE_handlers) do
    if name == 'draw' then
      love.draw = def
    elseif name == 'update' then
      love.update = def
    else
      love.handlers[name] = def
    end
  end
end

function love.update(dt)
  Slab.Update(dt)
  Slab.BeginWindow('code',{AutoSizeWindow=false, X=0,Y=0, W=W,H=H, IsOpen=true})
    if Slab.Input('EditBox',{Text=InputText, MultiLine=true, MultiLineW=W-10, W=W-10, H=H-6*LineHeight}) then
      InputText = Slab.GetInputText()
    end
    if Slab.Button('Run') then
      Error_message = nil
      load(InputText, 'editor')()
    end
  Slab.EndWindow()
end

function love.draw()
  Slab.Draw()
  if Error_message then
    love.graphics.setColor(1,0,0)
    love.graphics.print(Error_message, 10,H-4*LineHeight)
  end
end