selection.ml

datatype symbol = String of string;

datatype expr =   binOp of etype * binOps * etype
                | singleOp of ops * etype
                | Tuple of expr list
                | Selektion of etype * expr
                | Konditional of expr * expr * expr
                | Applikation of expr * expr
                | Abstraktion of symbol * expr
                | Fixpunkt of symbol * symbol * expr;