I added a √ operator, the sqrt function is still used internally, but now there is a problem, it affects the := and .. operators of the database

failed: regress/plpgsql_array, regress/plpgsql_call, regress/plpgsql_control, regress/plpgsql_domain, regress/plpgsql_record, regress/plpgsql_simple, regress/plpgsql_transaction, regress/plpgsql_trap, regress/plpgsql_varprops, regress/cube, regress/cube_sci, regress/name, regress/misc_sanity, regress/mvcc, regress/triggers, regress/subselect, regress/case, regress/aggregates, regress/arrays, regress/btree_index, regress/brin, regress/join_hash, regress/brin_bloom, regress/brin_multi, regress/incremental_sort, regress/stats_ext, regress/select_parallel, regress/indirect_toast, regress/plpgsql, regress/domain, regress/rangefuncs, regress/conversion, regress/alter_table, regress/xml, regress/partition_prune, regress/explain, regress/resultcache, regress/oidjoins, regress/fast_default, regress/stats, regress/plpgsql-toast