On Wed, Dec 13, 2017 at 6:11 PM, Ivan Pozdeev via Distutils-SIG wrote:

On 14.12.2017 3:17, Barry Warsaw wrote:

...

I'm about to release a new version of importlib_resources, so I want to get my flit.ini's require-python clause right. We support Python 2.7, and 3.4 and beyond. This makes me sad:

requires-python = '>=2.7,!=3.0,!=3.1,!=3.2,!=3.3'

Of course, I'd like to write this like:

requires-python = '(>=2.7 and <3) or >= 3.4'

I understand that OR clauses aren't supported under any syntax currently, but as PEPs 566 and 508 are still open/active, wouldn't it be reasonable to support something like this explicitly?

It seems like wanting to support 2.7 and some versions of Python 3 (but not all) is a fairly common need.

What you're actually asking for is for the >= operator to be limited to a specified major version.

We actually have the ~= operator that's basically that-- not sure if it's allowed in requires-python. But that's not sufficient. You also need an "or" primitive if you want to express "~= 2.7 or ~= 3.4". Right now all you could write is "~= 2.7 and ~= 3.4", which is the null set :-). -n -- Nathaniel J. Smith -- https://vorpus.org

On 14.12.2017 5:25, Nathaniel Smith wrote:

On Wed, Dec 13, 2017 at 6:11 PM, Ivan Pozdeev via Distutils-SIG wrote:

...

On 14.12.2017 3:17, Barry Warsaw wrote:

...

I'm about to release a new version of importlib_resources, so I want to get my flit.ini's require-python clause right. We support Python 2.7, and 3.4 and beyond. This makes me sad:

requires-python = '>=2.7,!=3.0,!=3.1,!=3.2,!=3.3'

Of course, I'd like to write this like:

requires-python = '(>=2.7 and <3) or >= 3.4'

I understand that OR clauses aren't supported under any syntax currently, but as PEPs 566 and 508 are still open/active, wouldn't it be reasonable to support something like this explicitly?

It seems like wanting to support 2.7 and some versions of Python 3 (but not all) is a fairly common need. What you're actually asking for is for the >= operator to be limited to a specified major version.

We actually have the ~= operator that's basically that-- not sure if it's allowed in requires-python. But that's not sufficient. You also need an "or" primitive if you want to express "~= 2.7 or ~= 3.4". Right now all you could write is "~= 2.7 and ~= 3.4", which is the null set :-). With the aforementioned semantic versioning, a "natural" version specifier would be:

* a disjuction of major versions (probably a range), * with each one of them possibly accompanied by a conjuction of minor versions. So, yes, for this, an `or' and superposition (arbitrary or otherwise) are absolute requirements. -- Regards, Ivan