Hi Ted,
> What I observe (which agrees with you) is:
>
> $A=B$
> --> "A = B"
> $A=-B$
> --> "A = -B$"
> $A = - B$
> --> "A = -B"
> $A~=~-B$
> --> "A = - B"
Some more samples that I've been playing with. Perhaps they'll help;
I'm out of time for now.
$ for e in '$a=b$' '$a~=~b$' '$a=-b$' '$a~=~-b$' '$a~=~type suppress - b$'
'$a={-b}$'; do
> printf '%s\t' "$e"
> eqn -d'$$' <<<"$e" | grep '^\.as1'
> done |
> column -s$'\t' -t
$a=b$ .as1 10
\&\E*[0sfont]\f[I]\s'\En[0ssize]u'\,a\/\h'28M'\f[R]\,\[eq]\/\fP\h'28M'\,b\/\E*[0rfont]
$a~=~b$ .as1 10
\&\E*[0sfont]\f[I]\s'\En[0ssize]u'\,a\/\h'28M'\f[R]\,\[eq]\/\fP\h'28M'\,b\/\E*[0rfont]
$a=-b$ .as1 10
\&\E*[0sfont]\f[I]\s'\En[0ssize]u'\,a\/\h'28M'\f[R]\,\[eq]\/\fP\h'28M'\f[R]\,\[mi]\/\fP\,b\/\E*[0rfont]
$a~=~-b$ .as1 10
\&\E*[0sfont]\f[I]\s'\En[0ssize]u'\,a\/\h'28M'\f[R]\,\[eq]\/\fP\h'28M'\f[R]\,\[mi]\/\fP\h'22M'\,b\/\E*[0rfont]
$a~=~type suppress - b$ .as1 10
\&\E*[0sfont]\f[I]\s'\En[0ssize]u'\,a\/\h'28M'\f[R]\,\[eq]\/\fP\h'28M'\f[R]\,\[mi]\/\fP\,b\/\E*[0rfont]
$a={-b}$ .as1 10
\&\E*[0sfont]\f[I]\s'\En[0ssize]u'\,a\/\h'28M'\f[R]\,\[eq]\/\fP\h'28M'\f[R]\,\[mi]\/\fP\,b\/\E*[0rfont]
$
Cheers, Ralph.
