[Sbcl-devel] map-dependents for non-class types

[Jim N. <jim...@gm...>]

Hi developers,

I’m using map-dependents/update-dependent to trigger cache updates which
certain classes change.  I wish there were a way to monitor when a type as
defined by typedef changes.   Certainly there is nothing in the MOP (as per
AMOP) which addresses this issue, but it seems to me like a very similar
problem.

That is, if my application needs to be notified when the type lattice
changes because a class has been redefined, then it might conceivably need
to be notified when a deftype is re-evaluated and has potentially changed
the type lattice.

Does sbcl have any way to handle this?  For example, is there a secret
class associated with a type created by deftype, or is there a meta-object
associated with a type-designator which is valid for add-dependent, and
map-dependents?

Since the mop-spec explicitly says that the situations in which
map-dependents is called is unspecified, it may be considered permissible
to trigger it when a type changes via deftype.

Any thoughts?

Jim