[Retr0spectrum]

Just playing around:

    import js
    c = js.globals.document.createElement("canvas")
    js.globals.document.body.appendChild(c)
    ctx = c.getContext("2d")
    ctx.fillRect(10, 10, 10, 10)

Edit: Here is a simple animation:

    import js
    import math
    import time
    c = js.globals.document.createElement("canvas")
    js.globals.document.body.appendChild(c)
    ctx = c.getContext("2d")
    
    def render():
      ctx.clearRect(0, 0, c.width, c.height)
      t = time.time()
      ctx.fillRect(20+math.sin(t*10)*10, 20+math.cos(t*10)*10, 10, 10)
    
    js.globals.window.setInterval(render, 20)

Here's a version you can paste in properly: http://pastebin.com/raw.php?i=67GadSUV

[fragmede]

Sadly, if I paste that in, I get:

    >>> import js 
    ... c = js.globals.document.createElement("canvas") 
    ... 
    debug: OperationError:
    debug:  operror-type: SyntaxError
    debug:  operror-value: ('EOL while scanning string literal', ('c callback', 1, 12, "r = c.push('import js\n", 0))
    debug: OperationError:
    debug:  operror-type: KeyError
    debug:  operror-value: 'r'

And then the input window hangs. Strangely enough, if I type it in instead, it's okay.

(ChromeOS v43 beta-channel)

[Retr0spectrum]

I think the only way around it is to paste each line separately. It seems to be caused by newline characters in the wrong place

[fragmede]

'that' refers to

    import js
    c = js.globals.document.createElement("canvas")

and not the pastebin. The pastebin works for me, but only the first time. Subsequent runs result in:

    <RuntimeError object at 0x15d648>
    RPython traceback:
      ...
    Fatal RPython error: