OT: typesafe callbacks in C (Re: [WIP PATCH 1/7] Add skeleton RA svnclient)

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Jun 25, 2010, 15:30 UTC
Message-ID: <20100625153031.GA9702@burratino>
In-Reply-To: <alpine.561.2.00.1006251412170.2144@daniel2.local>

Daniel Shahaf wrote:

Show 12 quoted lines

> By the way, a common pitfall is to mis-treat the void *baton argument as
> the wrong type of baton.  That is, code of the form
> 
>     f(void *baton) {
>         foo_baton_t *fb = baton;
>     }
> 
> instead of
> 
>     f(void *baton) {
>         bar_baton_t *bb = baton;
>     }

Just for kicks, I should mention

  http://ccan.ozlabs.org/info/typesafe_cb.html

which makes code like this cause warnings with gcc.

Maybe some version of Subversion years from now could use it.