boost_range/doc/reference/adaptors/indexed.qbk

[/
    Copyright 2010 Neil Groves
    Distributed under the Boost Software License, Version 1.0.
    (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
/]
[section:indexed indexed]

[table
    [[Syntax] [Code]]
    [[Pipe] [`rng | boost::adaptors::indexed(start_index)`]]
    [[Function] [`boost::adaptors::index(rng, start_index)`]]
]

* [*Returns:] A range adapted to return both the element and the associated index. The returned range consists of iterators that have in addition to the usual iterator member functions an `index()` member function that returns the appropriate index for the element in the sequence corresponding with the iterator.
* [*Range Category:] __single_pass_range__
* [*Range Return Type:] `boost::indexed_range<typeof(rng)>`
* [*Returned Range Category:] The range category of `rng`

[section:indexed_example indexed example]
[import ../../../test/adaptor_test/indexed_example.cpp]
[indexed_example]
[endsect]

This would produce the output:
``
Element = 10 Index = 0
Element = 20 Index = 1
Element = 30 Index = 2
Element = 40 Index = 3
Element = 50 Index = 4
Element = 60 Index = 5
Element = 70 Index = 6
Element = 80 Index = 7
Element = 90 Index = 8
``
[endsect]