Fix for incorrect overloaded assignment

Subject: Re: overloading problem

Jarkko Hietaniemi writes:
>
>
> Please proofread for me. Isn't what Chris is trying to do
>
> 	to get overloading to promote the unblessed scalar $c
> 	containing '2' to a Math::Complex blessed object?
>
> Please correct me if I am wrong but isn't this impossible?
>
> As there are only three possibilities for binops: normally ordered
> arguments, inverted arguments, modifying binop: the overloading will
> swap the honest Math::Complex $z as the first argument _and_ pass the
> third argument to minus() as undef (perldoc overload) and therefore
>
> 	a) the value of the result will be $z - $c, not $c - $z
> 	b) minus() will modify $z, not $c
>
> I may just too sleepy...

Looks like an overeager optimization... Try this:

p5p-msgid: 199704112225.SAA03482@monk.mps.ohio-state.edu

diff --git a/gv.c b/gv.c
index cc520d6..257f421 100644 (file)
--- a/gv.c
+++ b/gv.c
@@ -1301,7 +1301,7 @@ int flags;
     EXTEND(sp, notfound + 5);
     PUSHs(lr>0? right: left);
     PUSHs(lr>0? left: right);
-    PUSHs( assign ? &sv_undef : (lr>0? &sv_yes: &sv_no));
+    PUSHs( lr > 0 ? &sv_yes : ( assign ? &sv_undef : &sv_no ));
     if (notfound) {
       PUSHs( sv_2mortal(newSVpv((char *)AMG_names[method + assignshift],0)) );
     }