The constraint regular, see [CB04] and [P04], ensures that the sequence of values assigned to the variables it involves forms a word that can be recognized by a deterministic (or non-deterministic) finite automaton.
The syntax for regular is:
<regular> <list> (intVar wspace)+ </list> <transitions> ("(" state "," intVal "," state ")")+ </transitions> <start> state </start> <final> (state wspace)+ </final> </regular>
As an example, let us consider the constraint defined on scope
<regular> <list> x1 x2 x3 x4 x5 x6 x7 </list> <transitions> (a,0,a)(a,1,b)(b,1,c)(c,0,d)(d,0,d)(d,1,e)(e,0,e) </transitions> <start> a </start> <final> e </final> </regular>