[Boost-users] Re: enable_if question

From: David Abrahams (dave_at_[hidden])
Date: 2004-06-13 11:21:44

Howard Hinnant <hinnant_at_[hidden]> writes:

> And you might prefer to place the condition on the return type for
> readability purposes:
>
> template <class T>
> typename enable_if
> <
>      condition1 && condition2,
>      T
>  >::type
> foo(T t);

Ahem.  That would be:

  template <class T>
  typename enable_if
  <
       mpl::and_<condition1, condition2>,
       ^^^^^^^^^^
       T
   >::type
  foo(T t);

or, if you insist, the usually-less-efficient

  template <class T>
  typename enable_if_c
                    ^^
  <
       condition1::value && condition2::value,
       T
   >::type
  foo(T t);

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com