On Thursday, 30 November 2017 at 19:17:32 UTC, Jack Stouffer
wrote:
I'm starting work on a proposal for stdx.decimal, and one of
the clearest implementations to work off of is the Python
implementation.
This however, poses a problem because Python's source is under
the PSFL, a BSD-like permissive license. Any derivative work,
such as a D conversion, must have the original copyright
notice, a copy of the PSFL, as a well as a summary of changes.
This is simple enough to do, but the resulting code would be
dual-licensed with the PSFL and the BSL 1.0 (dual-licensing
being relatively common in other OSS projects).
My question is there any reason this could pose a problem?
Could this interfere with something like distribution or
company adoption?
Also note, one of the existing Phobos modules, std.net.isemail,
is supposed to be dual-licensed because it's derived from an
existing BSD work. But, it's missing the BSD license from the
top (and is technically breaking the license because of that).
I don't believe BSD or PSFL-licensed source can be dual-licensed
by you, unless you have the copyright on all the code yourself,
which appears to not be the case here. BSD-like licensed code is
often then simultaneously licensed as GPL by those who don't have
the copyright, while maintaining the original author's BSD
copyright notice, because the GPL is a more restrictive license
than the BSD license.
However, the Boost license is less restrictive than the BSD
license, so technically you would be breaking the license
attribution clause of the BSD license if you tried to
simultaneously apply the more permissive Boost license to it.
You could probably go the other way from less restrictive Boost
to more restrictive BSD though. And if you own the copyright,
you could actually dual-license as BSD/Boost, meaning the user
chooses one or the other, but nobody offers that combo because
they're both so permissive.
IANAL and this is all hazy legal territory, but I believe this is
the way it would commonly be technically interpreted, ie you
cannot do what you want and what was done with std.net.isemail,
if originally BSD like you describe, can't be done without the
explicit permission of the author.
