typeChanged

This function implements the HasType.TypeListener interface. We need to be really careful about type changes in the ConstructExpression. The problem is, that usually, a VariableDeclaration is registered as a type listener for its initializer, e.g, to infer the type of the variable declaration based on its literal initializer. BUT, if the initializer also implements HasType.TypeListener, as does ConstructExpression, the initializer is also registered as a type listener for the declaration. The reason for that is primary stemming from the way the C++ AST works where we need to get information about Integer i(4), in which the Integer type is only available to the declaration AST element and (4) which is the ConstructExpression does not have the type information.

Furthermore, there is a second source of type listening events coming from the CallResolver , more specifically, if CallExpression.invokes is set. In this case, the call target, i.e., the ConstructorDeclaration invokes this function here. We have to differentiate between those two, because in the second case we are not interested in the full FunctionDeclaration.type that propagates this change (which is a FunctionType, but only its FunctionDeclaration.returnTypes. This is already handled by CallExpression.typeChanged, so we can just delegate to that.

In fact, we could get rid of this particular implementation altogether, if we would somehow work around the first case in a different way.