On 02/10/2016 11:42 PM, Glenn Linderman wrote: > On 2/10/2016 2:20 PM, Georg Brandl wrote: >> This came up in python-ideas, and has met mostly positive comments, >> although the exact syntax rules are up for discussion. >> >> cheers, >> Georg >> >> -------------------------------------------------------------------------------- >> >> PEP: 515 >> Title: Underscores in Numeric Literals >> Version: $Revision$ >> Last-Modified: $Date$ >> Author: Georg Brandl >> Status: Draft >> Type: Standards Track >> Content-Type: text/x-rst >> Created: 10-Feb-2016 >> Python-Version: 3.6 >> >> Abstract and Rationale >> ====================== >> >> This PEP proposes to extend Python's syntax so that underscores can be used >> in >> integral and floating-point number literals. >> >> This is a common feature of other modern languages, and can aid readability >> of >> long literals, or literals whose value should clearly separate into parts, >> such >> as bytes or words in hexadecimal notation. >> >> Examples:: >> >> # grouping decimal numbers by thousands >> amount = 10_000_000.0 >> >> # grouping hexadecimal addresses by words >> addr = 0xDEAD_BEEF >> >> # grouping bits into bytes in a binary literal >> flags = 0b_0011_1111_0100_1110 > > +1 > > You don't mention potential restrictions that decimal numbers should permit > them > only every three places, or hex ones only every 2 or 4, and your binary > example > mentions grouping into bytes, but actually groups into nybbles. > > But such restrictions would be annoying: if it is useful to the coder to use > them, that is fine. But different situation may find other placements more > useful... particularly in binary, as it might want to match widths of various > bitfields. > > Adding that as a rejected consideration, with justifications, would be > helpful.
I added a short paragraph. Thanks for the feedback, Georg _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
