On 09/06/2021 19:35, Oliver Corff wrote:
> All .dot requests MUST be at the beginning of the line; in your code
> example, the dot is not recognized.
No, that is not so. The issue with Hans' example, (apart from the under
escaping of register references within his macro definitions, as Peter
has already noted), is that he is not specifying the appropriate end
marker for his .ig request. Since the effect of his SOLUTION macro ends
with a following SOLEND macro rather than:
> .de SOLUTION
> .if (\n[s] == 0) .ig ++
> .br
> ..
> .de SOLEND
> .++
> ..
he should have:
.de SOLUTION
. if (\\n[s] == 0) .ig SOLEND
. br
..
.de ENDSOL
. \" Any clean-up required, at end of solution.
..
This toy example does, for me, what I believe Hans is trying to achieve:
$ cat foo.roff
.pl 10
.in 5m
.nr QNR 0 1
.de QUESTION
. br
. ti -5m
. nop \Z'Q\\n+[QNR].'\h'5m'\c
..
.de SOLUTION
. ie '\\$1'' .ds SOLHT 3v
. el .ds SOLHT \\$1
. el '
. if !\\n[SOLUTIONS] .ig SOLEND
. br
. ti -5m
. nop \Z'A.'\h'5m'\c
..
.de SOLEND
. \" Insert any required code here,
. \" to adjust state after a solution;
. \" (e.g. to insert blank space,
. \" when solutions are hidden).
. ie \\n[SOLUTIONS] .sp
. el .sp \\*[SOLHT]
..
.QUESTION
Solutions are not normally shown.
How can they be made visible?
.SOLUTION 5v
Run the formatter,
specifying the "-rSOLUTIONS=1" register assignment,
on the command line.
.SOLEND
.
.in 0
.pl 1
Here is some arbitrary text, following the Q&A section.
$ nroff foo.roff
Q1. Solutions are not normally shown. How can they be made
visible?
Here is some arbitrary text, following the Q&A section.
$ nroff -rSOLUTIONS=1 foo.roff
Q1. Solutions are not normally shown. How can they be made
visible?
A. Run the formatter, specifying the "‐rSOLUTIONS=1" register
assignment, on the command line.
Here is some arbitrary text, following the Q&A section.
--
Regards,
Keith.
