Re: [Python-Dev] Importance of "async" keyword
On 3 July 2015 at 06:55, Sven R. Kunze wrote: > My understanding of coloring is "needs special treatment". > > Being special or not (containing an 'await' or not), as long as I don't need > to care, I can call them either way (with 'await' or not) and each case > works sensibly that's fine with me. I'm afraid you're going to be disappointed in that regard, as wishing that event driven programs behaved more like synchronous programs is like wishing that complex numbers behaved like real numbers. There's an extra level of complexity that is being deliberately introduced in order to improve Python's ability to express certain kinds of algorithms, and it isn't effective to just try to wish that complexity away. The payoff is that code that otherwise needs to be written as a long series of disconnected callback chains (as has long been possible with Twisted) can instead be written to look more like comparable synchronous code (and this approach should bring with it much improved introspection support, at least in 3.5+ now that gi_yieldfrom and cr_await are being exposed at the Python level). > Sensible would be something similar to: > await function: suspension point and runs the function until completion > call awaitable: runs the awaitable until completion These both fail, and deliberately so: we don't know what they're supposed to mean, and we refuse the temptation to guess. They're also quite likely to indicate a bug (e.g. forgetting to call a native coroutine function to get the coroutine out of it, forgetting to wait for an awaitable) rather than something folks have done deliberately. It's possible shorthand adapters may emerge over time, like: # Call awaitable from synchronous code def wait_for_result(awaitable): """Usage: result = asyncio.wait_for_result(awaitable)""" return asyncio.get_event_loop().run_until_complete(awaitable.__await__()) # Call blocking operation from asynchronous code def blocking_call(f, *args, **kwds): """Usage: result = await asyncio.blocking_call(f, *args, **kwds))""" cb = functools.partial(f, *args, **kwds) return asyncio.get_event_loop().run_in_executor(cb) However, those can be written already as utility functions, so we can wait and see how strong the demand is for them as adapters. (They may also be potentially useful to have as recipes in the documentation) Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia ___ 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
[Python-Dev] Summary of Python tracker Issues
ACTIVITY SUMMARY (2015-06-26 - 2015-07-03) Python tracker at http://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue. Do NOT respond to this message. Issues counts and deltas: open4922 (+14) closed 31399 (+30) total 36321 (+44) Open issues with patches: 2255 Issues opened (27) == #3530: ast.NodeTransformer doc bug http://bugs.python.org/issue3530 reopened by terry.reedy #24400: Awaitable ABC incompatible with functools.singledispatch http://bugs.python.org/issue24400 reopened by r.david.murray #24458: Documentation for PEP 489 http://bugs.python.org/issue24458 reopened by ncoghlan #24518: json.dumps should accept key function for ``sort_keys`` http://bugs.python.org/issue24518 opened by catherinedevlin #24520: Stop using deprecated floating-point environment functions on http://bugs.python.org/issue24520 opened by Andrew Turner #24524: python crash using Tkinter http://bugs.python.org/issue24524 opened by tomnor #24525: [doc] missing word http://bugs.python.org/issue24525 opened by vincent-legoll #24527: The MimeTypes class cannot ignore global files per instance http://bugs.python.org/issue24527 opened by Sebastian Noack #24531: please document that no code preceding encoding declaration is http://bugs.python.org/issue24531 opened by jwilk #24532: asyncio.sock_recv() blocks normal ioloop actions. http://bugs.python.org/issue24532 opened by mmarkk #24533: Increased Test Coverage for Lib/random.py http://bugs.python.org/issue24533 opened by Charles Nodell #24536: os.pipe() should return a structsequence (or namedtuple.) http://bugs.python.org/issue24536 opened by jonathan.slenders #24538: os.setxattr PermissionError on panfs propagates up causing `co http://bugs.python.org/issue24538 opened by Gerrit.Holl #24539: StreamReaderProtocol.eof_received() should return True to keep http://bugs.python.org/issue24539 opened by gvanrossum #24540: Documentation about skipkeys parameter for json.dumps is incor http://bugs.python.org/issue24540 opened by Matthew Havard #24542: ssl - SSL_OP_NO_TICKET not reimplemented http://bugs.python.org/issue24542 opened by miniCruzer #24544: Race condition and crash when embedding multi-thread script http://bugs.python.org/issue24544 opened by Oleksiy Markovets #24545: Issue with ssl package http://bugs.python.org/issue24545 opened by kxl561 #24546: sequence index bug in random.choice http://bugs.python.org/issue24546 opened by Serge Anuchin #24548: Broken link in the unittest documentation http://bugs.python.org/issue24548 opened by wau #24549: string.format() should have a safe_substitute equivalent, to b http://bugs.python.org/issue24549 opened by azrdev #24550: maxint on 64 bit platforms breaks os.read http://bugs.python.org/issue24550 opened by Brian Mingus #24553: improve test coverage for subinterpreters http://bugs.python.org/issue24553 opened by eric.snow #24554: GC should happen when a subinterpreter is destroyed http://bugs.python.org/issue24554 opened by eric.snow #24555: Python logic error when deal with re and muti-threading http://bugs.python.org/issue24555 opened by bee13oy #24557: Refactor LibreSSL / EGD detection http://bugs.python.org/issue24557 opened by spil #24560: codecs.StreamReader doesn't work with nonblocking streams: Typ http://bugs.python.org/issue24560 opened by yac Most recent 15 issues with no replies (15) == #24560: codecs.StreamReader doesn't work with nonblocking streams: Typ http://bugs.python.org/issue24560 #24557: Refactor LibreSSL / EGD detection http://bugs.python.org/issue24557 #24550: maxint on 64 bit platforms breaks os.read http://bugs.python.org/issue24550 #24548: Broken link in the unittest documentation http://bugs.python.org/issue24548 #24542: ssl - SSL_OP_NO_TICKET not reimplemented http://bugs.python.org/issue24542 #24539: StreamReaderProtocol.eof_received() should return True to keep http://bugs.python.org/issue24539 #24527: The MimeTypes class cannot ignore global files per instance http://bugs.python.org/issue24527 #24525: [doc] missing word http://bugs.python.org/issue24525 #24524: python crash using Tkinter http://bugs.python.org/issue24524 #24520: Stop using deprecated floating-point environment functions on http://bugs.python.org/issue24520 #24512: multiprocessing should log a warning when forking multithreade http://bugs.python.org/issue24512 #24499: Python Installer text piles up during installation process http://bugs.python.org/issue24499 #24498: Should ptags and eptags be removed from repo? http://bugs.python.org/issue24498 #24477: In argparse subparser's option goes to parent parser http://bugs.python.org/issue24477 #24466: extend_path explanation in documentation is ambiguous http://bugs.python.org/issue24466 Most recent 15 issues waiting for review (15) = #24557: Refactor LibreSSL / EGD
