[Haskell-cafe] Re: ANN: hakyll-0.1

[minh thu]

2009/12/12 Stephen Tetley <stephen.tetley at gmail.com>:
> 2009/12/12 Tom Tobin <korpios at korpios.com>:
>
>>
>> 1) Can the author of Y legally distribute the *source* of Y under a
>> non-GPL license, such as the 3-clause BSD license or the MIT license?
>
> Hello Tom
>
> If the answer to this isn't yes, I'll buy a hat and eat it...
>
> As source, Y (the BSD3 library) can surely be distributed as the
> author sees fit. The author could even distribute Y as source under a
> non-GPL _compatible_ license. This would hamper the utility Y, neither
> the author of Y nor anyone else could distribute an executable that
> agglomerates X and Y, but I honestly can't see how the existence of
> library X (GPL) can make it illegal to distribute other distinct works
> (my emphasis on _distinct_).
>
> Now, author X could choose to sue author Y for copyright infringement.
> If such a case happened it might set the precedent for what a 'derived
> work' is - vis-a-vis GPL and libraries - from my cursory web
> searching, such a case hasn't happened. From the 'Linking and derived
> works' bit in the Wikipedia page, the judgement on copyright law notes
> "the infringing work must incorporate a portion of the copyrighted
> work in some form", surely the judges would have to decide whether or
> not calling API's and reusing datatypes is incorporation.
>
> http://en.wikipedia.org/wiki/GNU_General_Public_License
>
>
>> 3) If the answer to 1 is "yes", what specifically would trigger the
>> redistribution of a work in this scenario under the GPL?  Is it the
>> distribution of X+Y *together* (whether in source or binary form)?
>
> Don't know.
>
> In the case of Hakyll and other packages on Hackage, the distribution
> is in source form. If someone wanted to repackage the code from
> Hackage as a binary distro they would have different obligations.
>
>> 4) If the answer to 1 is "yes", does this mean that a "BSD-licensed"
>> library does not necessarily mean that closed-source software can be
>> distributed which is based upon such a library (if it so happens that
>> the library in turn depends on a copylefted library)?
>
> The 'closed-source' software here still depends on a 'copyleft'
> library - if the library is GPL then the terms of the GPL apply.
> Whether there is an intermediary BSD licensed library is surely
> immaterial.

I'd like to point out a possible situation, that makes the questions
even more interesting.

Say the author of Y (the BSD licensed code) is used to install its
code, Y, along of its requisite X (under GPL) to customer locations.
Note that Y and X are not (re)distributed in compiled form. In fact,
the client could have the internal resource to install and configure Y
and its requisite himself (if Y was made available to him).

Is it ok in regard of the GPL ?

Cheers,
Thu