Re: Using code from Cocotron

[Richard Frith-Macdonald]

On 11 May 2007, at 06:40, Yen-Ju Chen wrote:

> Hi,
>
>  I was looking at GNUstep's NSPredicate implementation
>  and one obvious missing part is the -evaluateWithObject: in
> NSComparisonPredicate.
>  Then I found Cocotron has more implementation than GNUstep.
>  Since NSPredicate use KVC and I remember
>  GNUstep's implementation of KVC/KVO is not finished (It is listed in
> SoC 2007 for GNUstep),

KVC is complete, but IMO is sufficiently underused/tested that it may  
contain bugs, which is why I'd like to see it reviewed.
KVO is not complete, but is not (afaik) used by the NSPredicate stuff.

>  I look at Cocotron's implementation again and it seems to have
> implementation to an extent.
>  I wonder what is GNUstep's stand of using Cocotron's code
>  considering they are released under MIT ?

We can't use the code because they won't assign the copyright to the  
FSF.  in practice we probably couldn't use much (if any) of it simply  
anyway as we have our own codebase and cocotron stuff would need to  
be altered to fit in to gnustep.   Where it's valuable is that you  
can look at the cocotron code, see how they do things, and write code  
using ideas from it where appropriate (or write different code if you  
think they've gone wrong of course).

>  While their AppKit might be tied with Windows, Foundation should be
> fairly portable.
>  Something like nib supporting from Cocotron may also be worth to  
> take a look.
>  The point is that if license is not an issue and it will make
> GNUstep more complete,
>  why not take this advantage. :)

Well, as far as I know the license is an issue (I believe BSD is  
incompatible with the LGLP), and the cocotron people won't assign  
copyright, so we can't just incorporate the code for license/ 
copyright reasons.

I see at least four reasons why we can't just copy cocotron code:
1. it would need modifying to work
2. copyright
3. license
4. a minor problem ... coding style (needs reformatting etc to ,meet  
coding standards)

What you should do is write new code for GNUstep using ideas from  
cocotron as appropriate.  For that cocotron is obviously a valuable  
resource.