Postgresql command to drop a role after removing all privileges in a loop

postgresql-drop-role-loop.sql

/* This function loops over all schemas and drops a role's
   privileges in those schemas and then drops the role. Call
   it like `SELECT drop_role('foo');` where 'foo' is the role
   you want to drop. Would be nice to have exception handling
   😎😜
   
   Inspiration:
   https://stackoverflow.com/questions/3023583/how-to-quickly-drop-a-user-with-existing-privileges
*/

DROP FUNCTION IF EXISTS drop_role;
CREATE OR REPLACE FUNCTION drop_role(role_name TEXT) RETURNS void AS 
$$
DECLARE
    t record;
BEGIN
    FOR t IN
    SELECT DISTINCT(schema_name)
    FROM information_schema.schemata
    where schema_name not in ('pg_catalog', 'information_schema')
    LOOP
    EXECUTE format('REVOKE ALL PRIVILEGES ON ALL TABLES IN SCHEMA %I FROM %I', t.schema_name, role_name);
    EXECUTE format('REVOKE ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA %I FROM %I', t.schema_name, role_name);
    EXECUTE format('REVOKE ALL PRIVILEGES ON ALL FUNCTIONS IN SCHEMA %I FROM %I', t.schema_name, role_name);
    EXECUTE format('REVOKE ALL PRIVILEGES ON SCHEMA %I FROM %I', t.schema_name, role_name);
    END LOOP;
    EXECUTE format('DROP ROLE %I', role_name);
END;
$$ LANGUAGE plpgsql;