The *** combinator implements the algebra cross product. It can be used to derive the optimal score together with the candidates that produce it.

The standard algebras:

• enum:The enumeration algebra implements the enumeration of all candidates of a particular problem instance.
• prettyprint:The pretty printing algebra enumerates the candidates in a user friendly form.
• count:The counting algebra computes the size of the search space, in a way much more efficient than by enumeration. Note the invariance [length(grammar enum z)] = grammar count z.

See the source code for other algebras.