Add DSLD facility to declare compile-time errors and warnings based on pointcuts

One of the really useful features of Aspectj pointcuts is the ability to declare compile-time errors and warnings. An example of there use can be found here:

http://www.eclipse.org/aspectj/doc/released/adk15notebook/annotations-decp.html#declare-error-and-declare-warning

This facility would be very useful for the development and use of DSLDs. One can image using this feature to warn the user of incorrect DSLD usage. This would be very useful for hierarchical builder DSLs where the DSL author would like to report errors similar to those caused by improper xml structure with respect to an xsd file.

I'm not sure if this is possible right now, but it would add tremendous value.