We could solve this the way we save other things in tbl: by creating registers and laboriously populating and restoring from them.

But there are a lot of "previous-value" parameters that would require this approach.

• previously selected font mounting position (this one)
• previous default font family
• previous fill color
• previous stroke color
• previous indentation amount
• previous line length
• previous additional interline skip amount ("line spacing")
• previous title line length
• previous page offset
• previous type size
• previous post-vertical line spacing
• previous vertical spacing

While conceptually straightforward to do, the quantity of manual operations implied here suggests that it's a poor approach.

Further, off the top of my head, all of these are properties of the environment.

I therefore reiterate that it would probably be a good idea if GNU tbl produced output that created an environment for each table region.

So, input like this:

.TS
L.
hello
.TE

...would become something like this.

.TS
.ev 3tbl*environment
.evc \n[.ev]
...
.ev
.TE

Hmm, maybe James Clark hadn't invented the `.ev` register yet at the time he implemented GNU tbl.  I think I've speculated elsewhere that maybe he was trying to keep AT&T compatible output.  (That would explain why the name of every *roff object handled by GNU tbl has its name indirected through a C/C++ preprocessor macro.)  But it would appear that once the bridge was crossed to using long names for these, no one ever went back.  There's no mention I know of for a build option to use AT&T-legal names in GNU tbl output, and  as far as I recall, no support in GNU tbl code for generating AT&T-compatible escape sequences (e.g., `\n(xx` vs. `\n[.xx]`).

Anyway.  To solve this I think creating an environment is the way to go.

Urgency is not high.  As far as I know I am the first person to ever complain about this.

https://github.com/NetHack/NetHack/commit/9658f6769d1bded85f72e7b5b0f6a0841ef3604b