I don't like the fact that the value of the parameters associated with the Caller* attributes can be overriden by callers because they're implemented as a speci

I don't like the fact that the value of the parameters associated with the Caller* attributes can be overriden by callers because they're implemented as a special case of optional parameters. On the other hand, if the mechanism by which the Caller* attributes work is extensible, it may be interesting to use the feature to provide alternate default values for arbitrary optional params (e.g. non-const default values). On the other other hand, maybe changing the semantics of default value assignment is a symptomatic of language bloat.