Re: [Boost-users] [Boost.Fusion] Compile-time callbacks.

From: Stjepan Rajko (stipe_at_[hidden])
Date: 2008-07-29 21:52:15

On Tue, Jul 29, 2008 at 5:34 PM, Vjekoslav Brajkovic
<balkan_at_[hidden]> wrote:
>
> As I have sad before, I'm not particularly familiar with MPL/Fusion, so any
> clarifications are very welcome. For instance, the document specifies:
> "It is named "fusion" because the library is reminiscent of the "fusion"
> of compile time meta-programming with runtime programming.", but it does
> not specify which part is compile and which is run-time.
>

The types are compile-time and the values are run-time.  With most
fusion containers (say, fusion::vector<int,float>), each element has a
compile time type and a value that can be changed at run-time (this is
where it differs from MPL).   Maps/pairs are a slight departure from
the rest in that the first element of a fusion::pair (the key) does
not have a value associated with it, only the type.

Stjepan