Re: [help-texinfo] Using @image with @value gives an error

[Gavin Smith]

On Sun, Jul 21, 2019 at 02:57:13PM +0200, Christopher Dimech wrote:
> 
> I have noticed that the following commands works well
> 
> @center @image{../umrq3--files/E--ExecSm/309E--a01,11cm,,,.png}
> 
> 
> However the following one gives an error
> 
> @set upath ../umrq3--files/E--ExecSm
> @center @image{@value{upath}/309E--a01,11cm,,,.png}

This could possibly be fixed by making @value "completely expandable" in 
TeX terminology, e.g. the following change:

diff --git a/doc/texinfo.tex b/doc/texinfo.tex
index ed3f0ee..3b4018e 100644
--- a/doc/texinfo.tex
+++ b/doc/texinfo.tex
@@ -4681,6 +4681,8 @@ end
   \fi
 }
 
+\let\value\dummyvalue
+
 % Used for @value's in index entries to form the sort key: expand the @value
 % if possible, otherwise sort late.
 \def\indexnofontsvalue#1{%

would work in your case, I believe.  However, use of '-' and '_' in flag names
would be completely broken.  The Texinfo manual already states:

> However, it is best to use only
> letters and numerals in a flag name, not '-' or '_' or others--they will
> work in some contexts, but not all, due to limitations in TeX.

but there is a risk that somebody is currently using these in a flag 
name without problems and changing it would break things for them.

One idea that might work for you is to put the path to the directory in 
the TEXINPUTS environment variable, e.g.

  TEXINPUTS=$TEXINPUTS:../umrq3--files/E--ExecSm

This could be done in a Makefile that builds the documentation.  Then 
you may be able to simply use

  @center @image{309E--a01,11cm,,,.png}