On Wed, Sep 26, 2012 at 10:56 PM, Geoffrey Irving <irv...@naml.us> wrote: > On Wed, Sep 26, 2012 at 10:42 PM, Robert Bradshaw > <rober...@math.washington.edu> wrote: >> On Wed, Sep 26, 2012 at 8:54 PM, Geoffrey Irving <irv...@naml.us> wrote: >>> On Wed, Sep 26, 2012 at 6:03 PM, Robert Bradshaw >>> <rober...@math.washington.edu> wrote: >>>> On Wed, Sep 26, 2012 at 4:28 PM, Geoffrey Irving <irv...@naml.us> wrote: >>>>> Hello, >>>>> >>>>> I recently used sage to write a code generation script for exact >>>>> geometric predicates: >>>>> >>>>> https://github.com/otherlab/simplicity >>>>> >>>>> Since it's a python script that imports sage, the simplicity script is >>>>> GPL. >>>> >>>> Not automatically; often Sage is used more as an interpreter than a >>>> library: >>>> http://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html#IfInterpreterIsGPL >>> >>> The opposite has been said in previous discussions on this mailing >>> list: like most GPL python libraries, including sage is amount to >>> linking against sage, which means the script doing the including must >>> be GPL. I'm fine with this situation. >> >> The snippet you posted doesn't "link against" Sage anymore than >> Python. I don't hold with the philosophy that all Sage worksheets are >> automatically GPL. What about snippets of Sage code used as examples >> in published works? I'm not a lawyer, but as far as I know not even >> the lawyers have hashed this out. > > Here's an example of a thread with people voicing opinions in either > direction (this one in favor of copyleft): > > http://www.mail-archive.com/sage-devel@googlegroups.com/msg23091.html
Yes, I was an active participant in that thread, http://www.mail-archive.com/sage-devel@googlegroups.com/msg23126.html I don't think much has changed since then. > Unfortunately, in this situation I have to assume the worst, > especially if the lawyers haven't hashed it out. Well, it's a question of ascertaining the risk. I think the risk is low (that is the risk this being an actual violation as decided by the courts, let alone the risk of actually being taken to court on it). The more important factor is respecting the intent of the community, which you're clearly trying to do. >> As another data point, the GNU Bison project has an exception, but >> links in pure GPL libraries (iconv) that don't make mention of any >> exception. My hypothesis is that this is OK because the part of the >> source included in the output is part of Bison, not iconv. > > That's a good point, and would apply to my case as well (all the > copied snippets are bits of C++ code unrelated to Sage). Not sure if > I get it by the lawyers, but definitely worth a try. Thanks! (To go to one extreem, I suppose one could put all the C++ code strings in a separate file and call them a second input to your program, after all they're more data than code.) >>>> That being said, a runtime exemption could make a lot of sense, e.g. >>>> if we want to augment our fast_callable classes to spit out chunks of >>>> code in various languages. >>> >>> Okay. For now, it looks like the easiest way may be to port my code to >>> sympy. >> >> That may be a fine thing to do, but it's sad when legal fluff does >> nothing but add busywork... > > Agreed! Sage is a wonderful system, and it's a shame to not be able > to use it. On the other hand, copyleft certainly isn't legal fluff, > and people's choices should be respected. Oh, I agree. I'm talking about the corner cases like what line one needs to cross for a simple script to be considered a derived work and how that impacts re-distributing its output. I would be extremely surprised if any Sage developer morally objects to you licensing this output as you wish (though opinions may vary widely as to its legality). - Robert -- You received this message because you are subscribed to the Google Groups "sage-support" group. To post to this group, send email to sage-support@googlegroups.com. To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support?hl=en.
