Re: macro returning a value?

[Ulrich Lauther]

On Sun, Nov 14, 2021 at 12:33:38PM +0100, Ulrich Lauther wrote:
> On Sat, Nov 13, 2021 at 12:19:09PM -0500, Peter Schaffter wrote:
> > On Sat, Nov 13, 2021, Ulrich Lauther wrote:
> > > Is there a trick to make a macro or string return a value?
snip
> >   .de Pos
> >   \R'foo (\\n[.d]-\\n[.v]*254+1)/72000'\\n[foo]mm/10
> >   ..
> > 
> > which allows you to enter
> > 
> >   position: \n[.d] units, \*[Pos].
> > 
> 
> Wow! Works nicely.
> 
> But why is "R" escaped only once? \\R works too.
> And I had to add a line ".sp -1v" at the end of the  macro; otherwise I get a
> blank line after position: ...
> 

I now found out that the space between "foo" and the openening bracket causes 
the unintended blank line.
But why?

        ulrich

-- 
        -lauther