---- Reported by atsushi@ximian.com 2005-10-12 04:23:50 MST ----

mcs raises an error CS0408 when there is a set of overloaded methods one of
that takes such arguments of  a generic parameter type in the generic
class. However, it does not seem correct (see the last part of the
description below).

class Foo<T>
{
        public string this [int index] {
                get { return null; }
        }

        public string this [T key] {
                get { return null; }
        }
}

Actual Results:

possible-substitutes.cs(7,16): error CS0408: `Foo<T>' cannot define
overload members that may unify for some type parameter substitutions

Expected Results:

no CS0408 error.

How often does this happen? 

consistently.

Additional Information:

Here is an excerpt from ECMA 334.

25.1.7 Overloading in generic classes
Methods, constructors, indexers, and operators within a generic class
declaration can be overloaded. While
signatures as declared must be unique, it is possible that substitution of
type arguments results in identical
signatures. The tie-breaking rules of overload resolution will pick the
most specific one.

csc compiles it as I expected from above.



---- Additional Comments From atsushi@ximian.com 2005-10-18 00:38:19 MST ----

The latest msdn documentation does not have CS0408 error case - maybe
it is just removed?



---- Additional Comments From martin@ximian.com 2005-10-19 14:09:55 MST ----

This change has been made in the spec around November 2004; the CS0408
error doesn't exist anymore.



---- Additional Comments From martin@ximian.com 2005-10-19 14:10:36 MST ----

Low priority - it may be a lot of work to implement this.  However,
I'll try to figure out how much work exactly it'll be next week.



---- Additional Comments From terry@triplett.org 2006-01-16 12:00:45 MST ----

*Bump*

"I'll try to figure out how much work exactly it'll be next week."

Was wondering what the outcome was?  Just ran into this bug in a
real-world context while updating a (cross-platform) codebase to use
Generics and was hoping it would be addressed in the bug-fixing push
towards Mono 1.2.



---- Additional Comments From martin@ximian.com 2006-01-18 11:39:52 MST ----

Fixed in SVN.

The runtime part is in r55726, the gmcs changes and tests are in
r55728 and a required compiler-tester change is in r55727.

Removed gcs408*.cs and added gtest-236, gtest-237, gtest-238 and
gtest-239.



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