The interface in question will be used by cql type parser to get user
types. There are already three possible implementations of it:
- dummy, when no user types are in use (e.g. tests)
- schema-loader one, which gets user types from keyspaces that are
collected on its implementation of the database
- replica::database one, which does the same, but uses the real
database instance and that will be shared between scema_ctxts
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
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