Consistently model all pattern bindings in the scope map, as well as
having specific nodes for their initializers. This provides us with
more consistency (the declarations are represented) as well as giving
us a scope we can use to extract the DeclContext for a non-local
initializer.
Given a source location, we can find the innermost enclosing scope
that describes that source location. Introduce this operation into the
scope map, then add a testing mode where we probe the scope map at
specifi locations to see what we find. Test for:
1) Finding the right innermost enclosing scope, and
2) That we're only expanding the part of the scope map that is needed
to identify that scope.
* A child to evaluate the conditions, which covers expressions in the conditions
* A child for the 'else' body, which does not have access to the names in the conditions
* A child for the continuation, which re-introduces the names in the conditions for the rest of the body
Now we can assert that the only out-of-order case is for accessors.
The scope map models all of the name lookup scopes within a source
file. It can be queried by source location to find the innermost scope
that contains that source location. Then, one can follow the parent
pointers in the scope to enumerate the enclosing scopes.
The scope map itself is lazily constructed, only creating scope map
nodes when required implicitly (e.g, when searching for a particular
innermost scope) or forced for debugging purposes.
using a lazily-constructed tree that can be searched by source
location. A search within a particular source location will
