On Fri, Sep 14, 2018 at 7:18 PM, Antoon Pardon <antoon.par...@vub.be> wrote: > On 14-09-18 10:29, Chris Angelico wrote: >> On Fri, Sep 14, 2018 at 5:25 PM, Antoon Pardon <antoon.par...@vub.be> wrote: >>> >>> ... Suppose I have two threads, one in which I need >>> a precision of 3 and the other in which I need a precision of 7. In what >>> circumstances is it needed to use threads-locals to accomplish this and >>> how do I accomplish this? >>> >>> If I want my decimal code be usable with threads, how should I write it? >> Let's say both of those threads call the same function, which does this: >> >> def f(x, y): >> return x * 3 + y / 4 >> >> You can't pass a context as a parameter, so you have to set the >> context externally. Which is done thus: >> >> https://docs.python.org/3/library/decimal.html#decimal.setcontext >> >> Note that this sets it *for the current thread*. > > So, if I understand correctly, the threads-local information in this case is > part of the decimal implementation, so that the right context/precision is > used for the right thread. >
Correct, though it's an exposed part of the API too, so it's not "implementation detail" in the sense that it could be changed easily. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
