remove_if

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##### remove_if

###### Description

Returns a new sequence, containing all the elements of the original except those where a given unary function object evaluates to `true`.

###### Synopsis

    template<
        typename Pred,
        typename Sequence
        >
    typename result_of::remove_if<Sequence const, Pred>::type remove_if(Sequence const& seq);

Table 1.60. Parameters

Parameter | Requirement | Description
--- | --- | ---
`seq` | A model of Forward Sequence | Operation's argument
`Pred` | A model of unary MPL Lambda Expression | Removal predicate

###### Expression Semantics

    remove_if<Pred>(seq);

Return type: A model of Forward Sequence.

Semantics: Returns a new sequence, containing all the elements of `seq`, in their original order, except those elements with types for which `Pred` evaluates to `boost::mpl::true_`. Equivalent to ``filter`<boost::mpl::not_<Pred> >(seq)`.

###### Complexity

Constant. Returns a view which is lazily evaluated.

###### Header

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

###### Example

    const vector<int,double> vec(1,2.0);
    assert(remove_if<is_floating_point<mpl::_> >(vec) == make_vector(1));