https://github.com/python/cpython/commit/843bf42aa65aaa25b356e7b3d8733a117b8... commit: 843bf42aa65aaa25b356e7b3d8733a117b8f01a4 branch: master author: Guido van Rossum <guido@python.org> committer: Pablo Galindo <Pablogsal@gmail.com> date: 2019-04-29T13:49:29+01:00 summary: Add initial 'whatsnew' section for PEP 570 (GH-12942) files: M Doc/whatsnew/3.8.rst diff --git a/Doc/whatsnew/3.8.rst b/Doc/whatsnew/3.8.rst index 90ff72f67ff4..225faf8c0b7a 100644 --- a/Doc/whatsnew/3.8.rst +++ b/Doc/whatsnew/3.8.rst @@ -83,6 +83,31 @@ See :pep:`572` for a full description. .. TODO: Emily will sprint on docs at PyCon US 2019. +Positional-only parameters +-------------------------- + +There is new syntax (``/``) to indicate that some function parameters +must be specified positionally (i.e., cannot be used as keyword +arguments). This is the same notation as shown by ``help()`` for +functions implemented in C (produced by Larry Hastings' "Argument +Clinic" tool). Example:: + + def pow(x, y, z=None, /): + r = x**y + if z is not None: + r %= z + return r + +Now ``pow(2, 10)`` and ``pow(2, 10, 17)`` are valid calls, but +``pow(x=2, y=10)`` and ``pow(2, 10, z=17)`` are invalid. + +See :pep:`570` for a full description. + +(Contributed by Pablo Galindo in :issue:`36540`.) + +.. TODO: Pablo will sprint on docs at PyCon US 2019. + + Parallel filesystem cache for compiled bytecode files -----------------------------------------------------