[Larceny-users] ffi support for Integer to float

[Felix Klock]

Ed (cc'ing larceny-users)-

On Feb 10, 2009, at 2:41 PM, Eduardo Cavazos wrote:

> Felix Klock wrote:
>
>> I use Larceny's define-c-info form to extract
>> the various constants from the header file
>
> One drawback to 'define-c-info' is the dependency on a header file.  
> It's
> common for operating systems to have a library file (.so or .dll)
> available but not the corresponding header.

That's absolutely true; the intended development model is that the  
developer hooking into the foreign code (and who is supposed to have  
these headers installed) is the one using define-c-info; the developer  
is then expected to ship compiled .fasl files to the end-client as  
part of the complete library interfacing with the foreign code.

This "drawback" is hard to avoid in most cases; foreign libraries that  
require references to constants but do not standardize their values  
(nor provide procedural interfaces to extract their values) require  
someone in the development chain to extract information from the  
header file in some manner.

OpenGL falls under the category of a foreign library that standardizes  
the values of relevant constants in the interface.  OpenGL strikes me  
as a library that was designed to be accessed from a large family of  
languages (as opposed to just C).  So using define-c-info is not  
necessary here; I did not mean to imply otherwise.

-Felix