Wrap keywords that were \terminal{} with \keyword{} instead

[ilazaric]

My impression is that keywords should be \keyword{<string>} usually, no surrounding command, except in one of grammar definitions, where they should be wrapped in a \terminal{...}

Didn't do this on a couple occurences in preprocessor.tex (if and else are in \terminal{} args):

\begin{bnf}\obeyspaces
\nontermdef{else-group}\br
    \terminal{\# else   } new-line \opt{group}
\end{bnf}

\begin{ncsimplebnf}\obeyspaces
\indextext{\idxcode{\#if}}%
\terminal{\# if     } constant-expression new-line \opt{group}\br
\indextext{\idxcode{\#elif}}%
\terminal{\# elif   } constant-expression new-line \opt{group}
\end{ncsimplebnf}

\begin{bnf}\obeyspaces
\nontermdef{if-group}\br
    \terminal{\# if     } constant-expression new-line \opt{group}\br
    \terminal{\# ifdef  } identifier new-line \opt{group}\br
    \terminal{\# ifndef } identifier new-line \opt{group}
\end{bnf}

I don't think these are quite the same meaning as keyword if

Also, there are many instances of keywords not being \keyword-ed in \tcode{} parts, this PR does not touch those

Additionally some minor cleanup

• expressions.tex: \keyword{U} -> \tcode{U}
• lex.tex: removed space between command and argument

[ilazaric]

Last commit fixes spacing in overloading.tex, bnf for operator (that I broke in previous commits to this PR)
I originally didn't realize the spacing was important
Rendered and it looks good:

[jensmaurer]

Looks good.

[jensmaurer]

Please rebase.

[tkoeppe]

@ilazaric: Could you please rebase?

[ilazaric]

Apologies
I've rebased and resolved conflicts
I regenerated std.pdf and spot checked the affected locations, looks good to me, example:

[jensmaurer]

Looks good.

[tkoeppe]

Could you tell me the correctly phrased commit message? It's OK to keep things in one commit, but we should state the affected subclauses. So something like "[foo.bar, xy.zw] Use "\keyword" instead of "\terminal"". (Don't worry about changing the commit, I can do that at application time. I would just appreciate you looking up the references.)

[ilazaric]

[expr.prim.lambda.capture], [expr.post.general]/1, [expr.await]/1, [expr.yield], [lex.bool], [lex.nullptr], [over.call.object]/2, [over.oper.general]/1, [cpp.include]/7, [stmt.return.coroutine], [stmt.return.coroutine]/2, [temp.res.general]/2

Note [stmt.return.coroutine] is changed in 0th and 2nd paragraph
Just FYI, if I didn't write a /number, it is because the change occurs before the first paragraph
I was considering writing /0 , but looking at git log this doesn't seem to be common practice

Alternate format:
[expr.prim.lambda.capture, expr.post.general/1, expr.await/1, expr.yield, lex.bool, lex.nullptr, over.call.object/2, over.oper.general/1, cpp.include/7, stmt.return.coroutine, stmt.return.coroutine/2, temp.res.general/2]

Alternate without paragraph numbers:
[expr.prim.lambda.capture, expr.post.general, expr.await, expr.yield, lex.bool, lex.nullptr, over.call.object, over.oper.general, cpp.include, stmt.return.coroutine, temp.res.general]