[boost] Re: intrusive tagging allows omision of unneeded headers

From: Dirk Gerrits (dirk_at_[hidden])
Date: 2003-01-08 12:15:35

Thorsten Ottosen wrote:
[snip]
> class X
> {
> public:
>     class tag {};
>     typedef tag X_tag;
       ^^^^^^^^^^^^^^^^^
> };
> 
> class bar
> {
> public:
>     class tag {};
>     typedef tag bar_tag;
       ^^^^^^^^^^^^^^^^^^^
> };

Why these typedefs? Why would one write X::X_tag instead of X::tag for 
example?

Dirk Gerrits