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fold
Description

Returns the result type of fold.

Synopsis
template<
    typename Sequence,
    typename State,
    typename F>
struct fold
{
    typedef unspecified type;
};

Table1.36.Parameters

Parameter

Requirement

Description

Sequence

A model of Forward Sequence

The sequence to iterate

State

Any type

The initial state for the first application of F

F

boost::result_of<F(E,S)>::type is the return type of f(e,s) for each element e of type E in seq, and current state s of type S

The operation to be applied on forward traversal


Expression Semantics
result_of::fold<Sequence, State, F>::type

Return type: Any type

Semantics: Returns the result of applying fold to a sequence of type Sequence, with an initial state of type State and binary function object or function pointer of type F.

Complexity

Linear, exactly result_of::size<Sequence>::value applications of F.

Header
#include <boost/fusion/algorithm/iteration/fold.hpp>
#include <boost/fusion/include/fold.hpp>

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