nl_tokens: - * fold : ( seq : Seq a | Array a z : b f : ( a () → b ) → b ) : b * &mdash ; polymorphic version of fold . Works with arrays too .
pl_tokens: function listFold ( list , z , f , n ) { if ( n < list . length ) { return f ( list [ n ] , function ( ) { return listFold ( <mask> , z , f , n + 1 ) ; } ) ; } else { return z ; } }