When is considerably altered code still under copyright.

That is a matter for an IP lawyer and will almost inevitably vary between jurisdictions. If you go down this route you and your client should take professional legal advice (which this post is not, FTAOD)

Which open source licences allow this approach?

AIUI, the BSD licence will allow you to change the code in any way for any purpose and to any degree you so choose. What it does not do is allow you to claim copyright for works which you have not created. Even if the code is released as public domain you cannot do that. eg. I cannot take Newton's Principia and claim copyright for it even though it is now in the public domain. I am not aware of any licence which will allow someone to claim copyright for something which they haven't written and nor would I expect anyone to release code under such a licence even if it did exist. If I annotate or edit Principia I can copyright my changes but not the original work.

In your shoes, I would point out to the client that they can either have the work without copyright transfer or that they can have it with but in the latter case it will cost them substantially more because you will not be able to base it upon the works of others.

But again, seek professional advice.

> But again, seek professional advice.

The commercial volume is too small to pay off legal advice. The payment is not my motivation.

They already have loads of content in other languages and I think Perl should be presented too.

> or that they can have it with but in the latter case it will cost them substantially more because you will not be able to base it upon the works of others.

That's already my approach, just wanted to learn more about licences.

From another perspective:

If I were a modules author I would not object to the reuse of code in the tutorial section.

Cheers Rolf
_{(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}

If I were a modules author I would not object to the reuse of code in the tutorial section.

Nor would I. However, I would strongly object to someone else claiming copyright of that code.

I am not aware of any licence which will allow someone to claim copyright for something which they haven't written

Transfers of Copyright are possible in the US. It's not something one normally finds in a software license, though.

Update: Looks like a software license would be insufficient to transfer a Copyright in the US because a signature is required.

IANAL of course but I'd contact the FSF or Creative Commons people and ask them (and/or ask them to refer you to an actual lawyer being subject matter expert for your locality). My guess is that it's going to be still considered a derivative work and you're not going to be able to completely reassign rights or terms independent of the underlying source's terms.

Maybe a bit beside what you actually ask, but I have no problem whatsoever in people *using* my code, abusing it or torturing it into corners I have never imagined.

I would however fiercely object to people using my code in (public) documentation or learning materials that alter the (layout of the) code. My code is beautiful as it is (subjective and I do not care if you disagree), and that should NOT be changed when using these documentation in teaching materials.

This is the reason I will never ever write (parts of a) book, as producers force ugly style and code layout and even uglier font defaults.

This is the reason I will never ever write (parts of a) book, as producers force ugly style and code layout and even uglier font defaults.

Has it ever been easier to self-publish? Donald Knuth shared your sentiments but he did something about it. Now you too can publish your own works leveraging the fruits of Knuth's labours. Of course this means either writing the whole book yourself or else finding contributors who share your preferences. Either way, I look forward to your magnum opus.

Ok I can live with that.

But please tell me

• Does this statement cover code in tutorials/how to sections?
• which licence do you use to enforce your wishes?

Cheers Rolf
_{(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}

I have no specific license for this (sadly). I also think that it would be hard to make legal.

Tutorials and how-to sections are documentation, and IMHO would fall under such a restriction.

Artistic license probably allows any reformatting. Anywhere.

I have never seen a license that enforces style and/or formatting. I also think that using such a licence would make many companies forbid the use of such code.

My wish is not to enforce my style on real-life code. My docs just should how *I* think it should be done most efficiently and most maintainable, but code and code style consistency in any project is way more important than the code (style) of a single sub/method/class.

However I would love to see the rest of the world to use my style, I know it is not going to happen. People think different.

My post was aimed at blogs, documentation, learning/teaching content that just copies from the documentation but then alters the style. However I understand that learning materials should also be consistent, I find this unacceptable.


Enjoy, Have FUN! H.Merijn

which licence do you use to enforce your wishes?

Copyright is what makes it illegal, not the license. As seen here, Copyright grants the exclusive right to prepare derivative works based upon the copyrighted work. Noone else is allowed to do with without first getting permission (in the form of a license).

Of course, open source licenses allows others to make modifications of the work, though they were often some conditions attached (inclusion of Copyright notice, inclusion of license, publication of the modified work until the same license, etc.