Build exclusion constraints USING INDEX

Hi,

I was wondering if there was any way to break down the creation of a new exclusion constraint into stages such that table locks most likely to affect performance during production hours are not taken.

Something like:

CREATE INDEX CONCURRENTLY new_index ON my_table USING gist (column1, column2, column3);
ALTER TABLE my_table ADD CONSTRAINT my_exclusion_constraint EXCLUDE USING INDEX new_index (column1 WITH &&, column2 WITH =, column3 WITH &&) NOT VALID;
ALTER TABLE my_table VALIDATE CONSTRAINT my_exclusion_constraint;

AFAICT nothing like the second statement is currently available, but I wanted to check that and see if there are any workarounds.

Thanks,
Steven.