I have a problem with template function operator +
(compiler: Borland C++ 5.0):

Declarations:

template <class A>
class E
{ ... };


class I
{ ... };

Two function templates:

template class <class A, class B>
'some complicated type' operator + (A &a, E<B> &b)   // template 1
{ ... }

template class <class A, class B>
'some complicated type' operator + (E<A> &a, B &b)    // template 2
{ ... }


I can add:

E<I> i;


'lvalue1' =  1 + i;   //  ok, template 1 used; number 1 is an
example,                 // it can be any type
 'lvalue2' =  i + 1;  //  ok, template 2 used

but when I try to add third function template

template class <class A, class B>
'some complicated type' operator + (E<A> &a, E<B> &b)  // template 3
{ ... }

and add somethig like this:

 'lvalue3' =  i + i;  //  error

there is ambiguity between templates 1 and 3.

I think that  template 3 could be some (partial?) specjalization of
tempalte 1 but how can it be expressed?

Can commpiler supporting partial specjalization of templates
compile something equivalent?

Jarek
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