[API UPDATE REQUEST] ProgressBar const progress reference

Hi all,
the progress bar seems to take a double reference. I think it should take a const double reference as it is not only just reading the progress from the reference, it should also guarantee not to change the actual progress while displaying it.
Since the value is only used internally its not a breaking api change.

Looking forward to hear what you think.
Best, Rincewind

This might a bit dangerous, as temporaries are allowed to be passed as const-refs. If a user accidentally passed a temporary double (which would be very easy to do!), the reference would dangle and they’d get crashes when the progress bar tried to read the current value.

You are absolutely right, I didn’t thought about that. I just noticed, that the ProgressBar is not sufficient for my use case anyway, as I need that to be an atomic double. So I’ll end up writing my own ProgressBar anyway.