src/server/pkg/collection/transaction.go
func (s *stm) cmps() []v3.Cmp {
	cmps := make([]v3.Cmp, 0, len(s.rset))
	for k, rk := range s.rset {
		cmps = append(cmps, isKeyCurrent(k, rk))
	}
	return cmps
}
func (s *stm) cmps() []v3.Cmp {
	cmps := make([]v3.Cmp, 0, len(s.rset))
	for k, rk := range s.rset {
		cmps = append(cmps, isKeyCurrent(k, rk))
	}
	return cmps
}
// cmps guards the txn from updates to read set