Introduce command line options --norepl and --nointeract, remove IsLIBGAP constant

[markuspf]

This is useful for "libgap" as introduced in #2702 and possibly using GAP in "batch mode" as one can leave out the QUIT_GAP(0); in GAP scripts.

This makes the IsLIBGAP constant obsolete, so we remove it as well.

[markuspf]

Could be two PRs but the two commits are trivial enough I think.

[ChrisJefferson]

Seems sensible, it's a thing I've wanted before actually, when running GAP from a script.

Super picky, should it be --norepl (or something like that) , just because you can still drop into the break loop and do things in there, which feels a bit like the shell, or should it automatically also enable --nobreakloop (do you want to always pair noshell with nobreakloop for your purposes?)

[ChrisJefferson]

Note, I'm happy for the option, and it's name, to be exactly what it is now, just wanted to see if it had been thought about :)

[markuspf]

I considered calling it --norepl, but the REPL is called Shell in GAP as far as I know;

You're right about the breakloop (when I tried it out here just now I ended up in the breakloop); For "libgap" purposes one would never want a break loop as far as I am concerned.

Not sure whether one wants --nointeractive or --batch that just disables both?

[codecov]

Codecov Report

Merging #2723 into master will decrease coverage by <.01%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master    #2723      +/-   ##
==========================================
- Coverage   75.78%   75.78%   -0.01%     
==========================================
  Files         478      478              
  Lines      241434   241438       +4     
==========================================
+ Hits       182974   182975       +1     
- Misses      58460    58463       +3

Impacted Files	Coverage Δ
lib/init.g	71.76% <ø> (ø)	⬆️
lib/system.g	66.66% <50%> (-0.32%)	⬇️
src/iostream.c	62.35% <0%> (-1.15%)	⬇️
src/stats.c	94.69% <0%> (-0.2%)	⬇️
hpcgap/lib/hpc/stdtasks.g	64.7% <0%> (+0.76%)	⬆️

[markuspf]

@ChrisJefferson I introduced --norepl and --nointeract; --norepl just disables the repl, but still gives you a break loop, whereas --nointeract disables all interaction (so it sets --norepl and --nobreakloop`).

[markuspf]

If anyone (maybe in particular @stevelinton @fingolfin @ChrisJefferson @sebasguts) has any opinions on the naming bikeshed (on these command line options), I am all ears.

[ChrisJefferson]

Those are fine names for me

[fingolfin]

There are people who don't know what a REPL is. There is also no help under ?REPL. Of course one can google, but I'd prefer if we did not force people to do that. Can we perhaps expand this, e.g. by writing "Disable the GAP read-eval-print loop (REPL)" or so?

[markuspf]

@fingolfin updated the help text, and rebased on current master.

I mentioned in the discussion before that "REPL" might not be as well-known a phrase as one might think, but also agreed with @ChrisJefferson that --noshell might be misunderstood to mean no interaction at all.