--- /dev/null
+(******************************************************)
+(* Claudio Sacerdoti Coen <sacerdot@cs.unibo.it> *)
+(* 14/05/2000 *)
+(******************************************************)
+
+type regexp =
+ Char of int
+ | Interval of int * int (* lower bound, upper bound *)
+ | Identifier of string
+ | Concat of regexp list list (* concatenation of disjunctions *)
+;;
+
+type definition = { id : string ; rel : regexp list } ;;