make an object read only

[dfh at forestfield.co.uk]

On Tuesday, 2 August 2016 16:13:01 UTC+1, Robin Becker  wrote:
> A reportlab user found he was doing the wrong thing by calling canvas.save 
> repeatedly, our documentation says you should not use Canvas objects after the 
> save method has been used. The user had mixed results :(
> 
> It would be better to make the canvas object completely immutable all the way 
> down when save has been called, ......
> 
> Is there a way to recursively turn everything immutable?
> -- 
> Robin Becker

Years ago I contributed a recipe to the O'Reilly Python Cookbook, 2nd Ed - 6.12 Checking an Instance for any State Changes. My original submission was rather more naive than that but Alex Martelli, one of the editors, rather took a fancy to the idea and knocked into the more presentable shape that got published. I'm wondering whether there would be any way of turning this idea around to achieve what you want.
--
Regards
David Hughes
Forestfield Software