Re: [boost] compile-time partial port of bind

From: Mat Marcus (mmarcus_at_[hidden])
Date: 2001-12-16 02:52:31

>----- Original Message -----
>From: "Mat Marcus" <mmarcus_at_[hidden]>
>
>>  Yes. Maybe a header file with a generalized n-ary function (like
>>  mpl::unaryfunction) could provide a good "broken compiler portable"
>>  idiom.
>
>What do you mean? I can't parse that.
>
>Sorry,
>Dave

Fair enough. Let me elaborate. MPL provides unary_function and 
binary_function, apparently for use in its original bind mechanism. 
(Aside: I am not really sure why Aleksey chose those names. I might 
lean towards something like EvalMF2 or lexical_closure, call, or 
apply). Anyway, one (anti-) refactoring that I use to help code 
compile under MSVC is to rewrite template argument dependent 
expressions such as:

       T::template apply<U>::type

like so:

       mpl::unary_function<T,U>::type

Similarly:

      T::template apply<U,V>::type

becomes:

       mpl::binary_function<T,U,V>::type

I was thinking that if n-ary_function's were added (perhaps using 
boost/preprocessor) to support a more general bind, then we could 
borrow them for the compiler workarounds as well. Of course now 
another compile-time bind mechanism is under development I'm not sure 
if mpl will still require n-ary_function's.

Mat