1[/ 2 Copyright 2010 Neil Groves 3 Distributed under the Boost Software License, Version 1.0. 4 (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 5/] 6[section:style_guide Terminology and style guidelines] 7 8The use of a consistent terminology is as important for __ranges__ and range-based algorithms as it is for iterators and iterator-based algorithms. If a conventional set of names are adopted, we can avoid misunderstandings and write generic function prototypes that are [*/self-documenting/]. 9 10Since ranges are characterized by a specific underlying iterator type, we get a type of range for each type of iterator. Hence we can speak of the following types of ranges: 11 12* [*/Value access/] category: 13 * Readable Range 14 * Writeable Range 15 * Swappable Range 16 * Lvalue Range 17* [*/Traversal/] category: 18 * __single_pass_range__ 19 * __forward_range__ 20 * __bidirectional_range__ 21 * __random_access_range__ 22 23Notice how we have used the categories from the __new_style_iterators__. 24 25Notice that an iterator (and therefore an range) has one [*/traversal/] property and one or more properties from the [*/value access/] category. So in reality we will mostly talk about mixtures such as 26 27* Random Access Readable Writeable Range 28* Forward Lvalue Range 29 30By convention, we should always specify the [*/traversal/] property first as done above. This seems reasonable since there will only be one [*/traversal/] property, but perhaps many [*/value access/] properties. 31 32It might, however, be reasonable to specify only one category if the other category does not matter. For example, the __iterator_range__ can be constructed from a Forward Range. This means that we do not care about what [*/value access/] properties the Range has. Similarly, a Readable Range will be one that has the lowest possible [*/traversal/] property (Single Pass). 33 34As another example, consider how we specify the interface of `std::sort()`. Algorithms are usually more cumbersome to specify the interface of since both [*/traversal/] and [*/value access/] properties must be exactly defined. The iterator-based version looks like this: 35 36`` 37 template< class RandomAccessTraversalReadableWritableIterator > 38 void sort( RandomAccessTraversalReadableWritableIterator first, 39 RandomAccessTraversalReadableWritableIterator last ); 40`` 41 42For ranges the interface becomes 43 44`` 45 template< class RandomAccessReadableWritableRange > 46 void sort( RandomAccessReadableWritableRange& r ); 47`` 48 49[endsect] 50 51