3 • A newtype cannot have an unlifted argument type
4 • In the definition of data constructor ‘MkA’
5 In the newtype declaration for ‘A’
7 T12729.hs:10:13: error:
8 • A newtype cannot have an unlifted argument type
9 • In the definition of data constructor ‘MkB’
10 In the newtype declaration for ‘B’