[patch] libstdc++/69240 generic operator!= for random number distributions

[Jonathan Wakely]

On 14/01/16 20:41 +0000, Jonathan Wakely wrote:
>On 14/01/16 20:57 +0100, Marc Glisse wrote:
>>Once you constrain, you could even use 'std' as the associated 
>>namespace ;-)
>
>True! And std is already an associated namespace of the standard
>distributions, so we wouldn't be making ADL look anywhere additional.


There is still an advantage to keeping the overloads isolated in their
own namespaces: they won't be shown as candidates when users try to
use == or != for types that aren't EqualityComparable. The errors for
the trivial testcase in PR69240 run to 365 lines, because of all the
possible operator== overloads that fail to match.

If the <random> operators are in a separate namespace they won't add
to the vast number of overloads in namespace std already.