def String.is_empty
import Base2036def String.is_empty(s: String) -> Bool:
2037 match s:
2038 case SNil{}:
2039 True{}
2040 case SCon{h, t}:
2041 False{}
import Base2036def String.is_empty(s: String) -> Bool:
2037 match s:
2038 case SNil{}:
2039 True{}
2040 case SCon{h, t}:
2041 False{}