> On Mon, Dec 21, 2009 at 4:59 PM, Luis Lavena <luislavena@gmail.com> wrote:

> > Wayne already answered to you that ffi_lib takes an array, multiple
> > invocations to append are not possible.

> 
> From the perspective of a new FFI API user, these are all valid
> questions with no immediate/clear answer:
> - What would happen on subsequent ffi_lib call? Will it append, or
> will it overwrite?
> - Is that even legal? If legal, is that a good practice?
> 
> I know I had those questions when I was starting using FFI. :) And I
> was bugging Wayne with such questions as well... :)
> 
> Looking at the ffi_lib code now, it is clear that subsequent ffi_lib
> calls are not good. Well, maybe we should make that totally explicit,
> and just don't allow to call ffi_lib the second time?
> 
> Thanks,
>   --Vladimri

Vladimir,

How about starting a Library wiki page to begin capturing key usage points like this for FFI::Library?  Yeh, I know you're already busy with JRuby but think I and others can help with tweaks :)

I think if we can continue to build up the wiki, especially for the core objects and usage patterns (and keep them up-to-date) it will go a long way to ease FFI startup costs.

One balancing challenge will be to keep them API-ish enough that they are applicable across the impls while highlighting (not overwhelming) impl-specific issues that may trip you up when trying to write a cross-impl and cross-platform FFI-based extension.

Jon