On Mon, Sep 4, 2017 at 2:50 PM, Koos Zevenhoven <k7hoven@gmail.com> wrote:
Hi all,
as promised, here is a draft PEP for context variable semantics and implementation. Apologies for the slight delay; I had a not-so-minor autosave accident and had to retype the majority of this first draft.
During the past years, there has been growing interest in something like task-local storage or async-local storage. This PEP proposes an alternative approach to solving the problems that are typically stated as motivation for such concepts.
From a quick skim, my impression is:
All the high-level semantics you suggest make sense... in fact, AFAICT they're exactly the same semantics we've been using as a litmus test for PEP 550. I think PEP 550 is sufficient to allow implementing all your proposed APIs (and that if it isn't, that's a bug in PEP 550). OTOH, your proposal doesn't provide any way to implement functions like decimal.setcontext or numpy.seterr, except by pushing a new state and never popping it, which leaks memory and permanently increases the N in the O(N) lookups. I didn't see any direct comparison with PEP 550 in your text (maybe I missed it). Why do you think this approach would be better than what's in PEP 550? -n -- Nathaniel J. Smith -- https://vorpus.org