Allow for implicit `this` expressions.

- When peforming ordinary lookup, if the container declaration for a scope is an aggregate type or `extension` decl, then use a "breadcrumb" to make sure that we use a `this` expression as the base of any resulting declaration reference

- Add a test case for implicit `this` usage

- Update constrained generic test case to use implicit `this` for member reference, as was originally intended

1 files changed, 6 insertions, 0 deletions

diff --git a/source/slang/syntax.h b/source/slang/syntax.h
index d32c4de15..0b5a38631 100644
--- a/source/slang/syntax.h
+++ b/source/slang/syntax.h
@@ -859,6 +859,12 @@ namespace Slang
                 // lookup was able to find a member through type `U`
                 // instead.
                 Constraint,
+
+                // The lookup process considered a member of an
+                // enclosing type as being in scope, so that any
+                // reference to that member needs to use a `this`
+                // expression as appropriate.
+                This,
             };
 
             // The kind of lookup step that was performed