[boost] Is there a special reason to use inline before template functions?

Subject: [boost] Is there a special reason to use inline before template functions?
From: Thomas Klimpel (Thomas.Klimpel_at_[hidden])
Date: 2008-12-07 18:48:13

Hi,

in boost, many template functions (but not all) use inline.
(Example from boost/accumulators/framework/accumulator_set.hpp that uses inline:
    template<typename Args>
    inline accumulator_visitor<Args> const make_accumulator_visitor(Args const &args)
    {
        return accumulator_visitor<Args>(args);
    }

Example from boost/algorithm/minmax.hpp hat doesn't use inline:
  template <typename T>
  tuple< T const&, T const& >
  minmax(T const& a, T const& b) {
    return (b<a) ? make_tuple(cref(b),cref(a)) : make_tuple(cref(a),cref(b));
  }
)

Is there a special reason why inline is used for template functions? I would expect that current compilers know better when inlining a function provides a benefit than the programmer. So I guess there is a better reason for using the inline keyword before template function than just speculative performance optimization, but I can't figure it out. Can anybody help me?

Most libs only prepend inline before template functions, but ublas prepends nearly every member function with the macro "BOOST_UBLAS_INLINE", which expands to "inline". Is there a reason why ublas uses this macro?

Regards,
Thomas