Method popAssert

dql/math.go:26–31

()

func (s *mathTreeStack) push(t *MathTree) { s.a = append(s.a, t) }

func (s *mathTreeStack) popAssert() *MathTree {
	x.AssertTruef(!s.empty(), "Expected a non-empty stack")
	last := s.a[len(s.a)-1]
	s.a = s.a[:len(s.a)-1]
	return last
}

func (s *mathTreeStack) pop() (*MathTree, error) {
	if s.empty() {