[Boost-users] MPL: Arguments to transform metafunction

Subject: [Boost-users] MPL: Arguments to transform metafunction
From: Missing Rainbow (d0253082_at_[hidden])
Date: 2008-10-15 12:46:14

Hi All,

I have a doubt regarding the arguments to the mpl::transform
metafunction.  In the MPL book (page 42), the mpl::transform is
presented as follows:

template <class Sequence1, class Sequence2, class BinaryOperation>
struct transform;

Here mpl::transform takes 2 sequences and a binary operation and it
results in a sequence.  But in a later portion of the book (page 124),
while discussing about sequence building algorithms, the following is
presented:

typedef mpl::vector_c<int, 1, 2, 3> v123;
typedef mpl::plus<_1, mpl::int_<5> > add5;
typedef mpl::transform<v123, add5>::type v678;

Here mpl::transform takes 1 sequence and a unary operation and it
results in a sequence.   How does mpl::transform supports such
different arguments?

Rgds,
anna