transform

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##### transform

###### Description

For a sequence `seq` and function object or function pointer `f`, `transform` returns a new sequence with elements created by applying `f(e)` to each element of `e` of `seq`.

###### Unary version synopsis

    template<
        typename Sequence,
        typename F
        >
    typename result_of::transform<Sequence const, F>::type transform(
        Sequence const& seq, F f);

Table 1.75. Parameters

Parameter | Requirement | Description
--- | --- | ---
`seq` | A model of Forward Sequence | Operation's argument
`f` | `f(e)` is a valid expression for each element `e` of `seq`. ``boost::result_of`<F(E)>::type` is the return type of `f` when called with a value of each element type `E`. | Transformation function

###### Expression Semantics

    transform(seq, f);

Return type: A model of Forward Sequence

Semantics: Returns a new sequence, containing the return values of `f(e)` for each element `e` within `seq`.

###### Binary version synopsis

    template<
        typename Sequence1,
        typename Sequence2,
        typename F
        >
    typename result_of::transform<Sequence1 const, Sequence2 const, F>::type transform(
        Sequence1 const& seq1, Sequence2 const& seq2, F f);

Table 1.76. Parameters

Parameter | Requirement | Description
--- | --- | ---
`seq1` | A model of Forward Sequence | Operation's argument
`seq2` | A model of Forward Sequence | Operation's argument
`f` | `f(e1,e2)` is a valid expression for each pair of elements `e1` of `seq1` and `e2` of `seq2`. ``boost::result_of`<F(E1,E2)>::type` is the return type of `f` when called with elements of type `E1` and `E2` | Transformation function

Return type: A model of Forward Sequence.

Semantics: Returns a new sequence, containing the return values of `f(e1, e2)` for each pair of elements `e1` and `e2` within `seq1` and `seq2` respectively.

###### Complexity

Constant. Returns a view which is lazily evaluated.

###### Header

    #include <boost/fusion/algorithm/transformation/transform.hpp>
    #include <boost/fusion/include/transform.hpp>

###### Example

    struct triple
    {
        typedef int result_type;

        int operator()(int t) const
        {
            return t * 3;
        };
    };
    ...
    assert(transform(make_vector(1,2,3), triple()) == make_vector(3,6,9));