possibly incorrect variable scoping

[Nitish-bot]

I was exploring L5 trying to write a mandelbrot set and I declare height and width variables when I found out there are global variables part of L5's internal state. The code can be found here

  -- global user vars - can be read by user but shouldn't be altered by user
  key = "" --default, overriden with key presses detected in love.update(dt)
  width = 800 --default, overridden with size() or fullscreen()
  height = 600 --ditto
  frameCount = 0
  mouseIsPressed = false
  mouseX=0
  mouseY=0
  keyIsPressed = false
  pmouseX,pmouseY,movedX,movedY=0,0
  mouseButton = nil
  focused = true
  pixels = {}

I feel like what we don't want the user manipulating , we shouldn't give them the ability to (not as easily at least). I might be missing something here but I think we can add them to L5_env table so if someone really wants to change these values they can but only if they know what they're doing.

[Nitish-bot]

I just realised I had to declare the variable locally but my question remains.

[lee2sman]

It is certainly not ideal for the user to be able to overrwrite them! But I'm not sure how to deal with this aspect of Lua and have it be compatible with Processing/p5's global vars. Those vars should be accessible by the end user for reading but not for writing. I've brainstormed but not tried an implementation out using a metatable on _G. But I'm a little wary of introducing unintended side effects.

[lee2sman]

@Nitish-bot a typical basic Processing/p5 style code sketch in L5 might make extensive use of these global vars, such as:

require 'L5'

function draw()
  
  fill(0,0,255)
  circle(width/2, height/2, 100)
  
  fill(0)
  circle(mouseX, mouseY, 30)
end