11 

    11 

    12 

    12 

    13 // more convenience for the map parsers later on;

    13 // more convenience for the map parsers later on;

    14 // it allows writing nested patterns as

    14 // it allows writing nested patterns as

    15 // case x ~ y ~ z => ...

    15 // case x ~ y ~ z => ...

    16 

    18 

    17 case class ~[+A, +B](x: A, y: B)

    19 case class ~[+A, +B](x: A, y: B)

    18 

    20 

    19 // constraint for the input

    21 // constraint for the input

    20 type IsSeq[A] = A => Seq[_]

    22 type IsSeq[A] = A => Seq[_]