Rob Stewart <stewart@sig.com> writes:
From: David Abrahams <dave@boost-consulting.com>
Rob Stewart <stewart@sig.com> writes:
What libraries are doing that? The authors might need a dope-slap. I hope it's not one of mine! ;-)
This isn't exhaustive, but here are a few examples that I found (I tried to skip related matches):
detail/atomic_count.hpp:83 detail/binary_search.hpp:34 detail/call_traits.hpp:32 detail/compressed_pair.hpp:39 detail/dynamic_bitset.hpp:26 detail/lwm_nop.hpp:23 detail/named_template_params.hpp:21 detail/quick_allocator.hpp:33 detail/shared_count.hpp:40 graph/adjacency_list.hpp:230 iterator/counting_iterator.hpp:24 pool/pool.hpp:71 test/execution_monitor.hpp:51 thread/condition.hpp:31 type_traits/add_pointer.hpp:19 utility/enable_if.hpp:78
I can't speak for all of these, but some of them are libraries that don't have their own namespace (e.g. enable_if). As long as enable_if is directly in namespace boost, it makes sense that its detail is in boost::detail. Whether or not enable_if should be in a subnamespace is a different fight. The same applies to iterator/counting_iterator.hpp, for example. The ones in detail/ are mostly components that were deemed to be of general utility within Boost but whose authors were not ready to give them a "public face" (i.e. review, documentation). They do not officially "belong" to any specific library and are often used across several libraries. Having them in boost::detail makes sense.
The following are examples in which another namespace is created inside boost::detail rather than a detail namespace within the library namespace. This keeps the names separate, but still seems inverted.
detail/allocator_utilities.hpp:23 function/function_base.hpp:106 multi_array/algorithm.hpp:46 variant/get.hpp:59
Yep, that's a little weird. I can say from experience that in a subnamespace of boost it can be awkward to have both boost::subnamespace::detail and boost::detail in scope, so it is sometime better to use another name (like aux:: a la MPL). -- Dave Abrahams Boost Consulting www.boost-consulting.com