withFile defeats dead handle closure

[Henning Thielemann]

On Wed, 30 Dec 2020, Ryan Trinkle via Libraries wrote:

> Although it might be nice to have a weak-reference-based alternative to
> withFile, I think it would be best to keep the behavior of withFile as
> predictable as possible (i.e. the current behavior), since closing a
> file can be semantically significant.

Right, if I open and close and re-open a file, it must be closed before I 
can re-open it.