{ $values { "alphabet""an alphabet of unique letters" } { "#""the maximum length" } }
{ $description "Defines stack shufflers of the form abc-bcba where 'abc' describes the inputs and 'bcba' describes the outputs. Given a stack of 1 2 3, this returns 2 3 2 1. The stack shufflers defined are put in the current vocab with the suffix '.shuffle' appended." }