Confusing MPL documentation regarding reverse_fold

[JUAN DENT]

Hi,

On my to understanding MPL Boost library, I have found something that seems an error of some sort.

Basically, dealing with mpl::reverse_fold, we get the following explanation:

typedef reverse_fold< s,state,backward_op,forward_op >::type t;

is said to be equivalent to:

typedef reverse_fold<
      Sequence
    , fold<s,state,forward_op>::type
    , backward_op
    >::type t;

but Sequence is not present in the first typedef!! So what is that?

Regards,
Juan