I've always assumed the AND and OR operators to be commutative and the SPDX Java tools take full advantage of the commutative properties when comparing license expressions.
I would welcome a pull request to Annex D to clarify this since at least one member of the community found this ambiguous and/or confusing. Gary > -----Original Message----- > From: Spdx-legal@lists.spdx.org <Spdx-legal@lists.spdx.org> On Behalf Of > Richard Fontana > Sent: Sunday, July 17, 2022 2:36 PM > To: J Lovejoy <opensou...@jilayne.com> > Cc: SPDX-legal <spdx-legal@lists.spdx.org> > Subject: Re: Commutativity of SPDX expressions > > The order of operations is a different issue, I think. I guess the SPDX spec > assumes, as you say, that commutativity of AND and OR is implicit (like > counterpart operations in propositional logic), but this implicit property was > not obvious to one Fedora contributor. > > Richard > > On Sun, Jul 17, 2022 at 4:08 PM J Lovejoy <opensou...@jilayne.com> wrote: > > > > Hi Richard, > > > > Annex D explains the order of precedence for the operators and use of > > parentheses. > > https://spdx.github.io/spdx-spec/SPDX-license-expressions/ > > > > I admit, I find the use of parentheses easier to understand overall (than > relying on remembering the order of precedence). > > > > I’m not sure it explicitly states that "MIT AND Apache-2.0" is equivalent to > "Apache-2.0 AND MIT” but I think that’s kind of implicit, no? > > > > I also think this entire annex could use a re-write to make it a bit > > more user-friendly (on the topic of improving documentation…) > > > > Jilayne > > > > > On Jul 17, 2022, at 12:21 PM, Richard Fontana <rfont...@redhat.com> > wrote: > > > > > > I'm working on some draft documentation for Fedora around use of > > > SPDX expressions in RPM spec file License: fields. I was surprised > > > to apparently not see anything in the SPDX spec that says that the > > > AND and OR operators are commutative. I want to assert that the > > > expression "MIT AND Apache-2.0" is equivalent to "Apache-2.0 AND > > > MIT". Does the SPDX spec actually take no position on this? > > > > > > Richard > > > > > > > > > > > > > > > > > > > > > > > > -=-=-=-=-=-=-=-=-=-=-=- Links: You receive all messages sent to this group. View/Reply Online (#3184): https://lists.spdx.org/g/Spdx-legal/message/3184 Mute This Topic: https://lists.spdx.org/mt/92443713/21656 Group Owner: spdx-legal+ow...@lists.spdx.org Unsubscribe: https://lists.spdx.org/g/Spdx-legal/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
