Re: [Boost-users] [fusion] runtime unsigned to a template argument compile-time unsigned

22 Feb 2010

      -----Original Message-----
From: "Larry Evans" [cppljevans@suddenlink.net]
Date: 22/02/2010 07:23 PM
To: boost-users@lists.boost.org
Subject: Re: [Boost-users] [fusion] runtime unsigned to a template argument
 compile-time unsigned

On 02/22/10 10:02, Larry Evans wrote:
...
On 02/21/10 05:27, Hicham Mouline wrote:
[snip]
...
...
3.       Can I generate an array of function pointers to the various 
at<>() functions and call the right one at runtime?
The 2 attached files show how this can be done.
Obviously, instead of:
typedef
      void(*
    method_type
    )(void)
    ;
you'd have:
typedef
      double(*
    method_type
    )(void)
    ;
This could even be done for heterogeneous return types; however,
in that case, a tagged variant.  The tag for this variant would
be the field index.  In the attached code, this would be something
like the super_numerals.

------------------------

This looks like it should go, already is in some library?

I have many places where I read the index, and I would like to use the index as the template argument,

thanks very much, will do,