| Ned Deily | 3a2883c | 2019-06-12 23:31:45 -0400 | [diff] [blame] | 1 | **************************** |
| 2 | What's New In Python 3.9 |
| 3 | **************************** |
| 4 | |
| 5 | :Release: |release| |
| 6 | :Date: |today| |
| 7 | |
| 8 | .. Rules for maintenance: |
| 9 | |
| 10 | * Anyone can add text to this document. Do not spend very much time |
| 11 | on the wording of your changes, because your text will probably |
| 12 | get rewritten to some degree. |
| 13 | |
| 14 | * The maintainer will go through Misc/NEWS periodically and add |
| 15 | changes; it's therefore more important to add your changes to |
| 16 | Misc/NEWS than to this file. |
| 17 | |
| 18 | * This is not a complete list of every single change; completeness |
| 19 | is the purpose of Misc/NEWS. Some changes I consider too small |
| 20 | or esoteric to include. If such a change is added to the text, |
| 21 | I'll just remove it. (This is another reason you shouldn't spend |
| 22 | too much time on writing your addition.) |
| 23 | |
| 24 | * If you want to draw your new text to the attention of the |
| 25 | maintainer, add 'XXX' to the beginning of the paragraph or |
| 26 | section. |
| 27 | |
| 28 | * It's OK to just add a fragmentary note about a change. For |
| 29 | example: "XXX Describe the transmogrify() function added to the |
| 30 | socket module." The maintainer will research the change and |
| 31 | write the necessary text. |
| 32 | |
| 33 | * You can comment out your additions if you like, but it's not |
| 34 | necessary (especially when a final release is some months away). |
| 35 | |
| 36 | * Credit the author of a patch or bugfix. Just the name is |
| 37 | sufficient; the e-mail address isn't necessary. |
| 38 | |
| 39 | * It's helpful to add the bug/patch number as a comment: |
| 40 | |
| 41 | XXX Describe the transmogrify() function added to the socket |
| 42 | module. |
| 43 | (Contributed by P.Y. Developer in :issue:`12345`.) |
| 44 | |
| 45 | This saves the maintainer the effort of going through the Mercurial log |
| 46 | when researching a change. |
| 47 | |
| 48 | This article explains the new features in Python 3.9, compared to 3.8. |
| 49 | |
| 50 | For full details, see the :source:`Misc/NEWS` file. |
| 51 | |
| 52 | .. note:: |
| 53 | |
| 54 | Prerelease users should be aware that this document is currently in draft |
| 55 | form. It will be updated substantially as Python 3.9 moves towards release, |
| 56 | so it's worth checking back even after reading earlier versions. |
| 57 | |
| 58 | |
| 59 | Summary -- Release highlights |
| 60 | ============================= |
| 61 | |
| 62 | .. This section singles out the most important changes in Python 3.9. |
| 63 | Brevity is key. |
| 64 | |
| 65 | |
| 66 | .. PEP-sized items next. |
| 67 | |
| 68 | |
| 69 | |
| 70 | New Features |
| 71 | ============ |
| 72 | |
| 73 | |
| 74 | |
| 75 | Other Language Changes |
| 76 | ====================== |
| 77 | |
| 78 | |
| 79 | |
| 80 | New Modules |
| 81 | =========== |
| 82 | |
| 83 | * None yet. |
| 84 | |
| 85 | |
| 86 | Improved Modules |
| 87 | ================ |
| 88 | |
| Victor Stinner | 066e5b1 | 2019-06-14 18:55:22 +0200 | [diff] [blame^] | 89 | threading |
| 90 | --------- |
| 91 | |
| 92 | In a subinterpreter, spawning a daemon thread now raises an exception. Daemon |
| 93 | threads were never supported in subinterpreters. Previously, the subinterpreter |
| 94 | finalization crashed with a Pyton fatal error if a daemon thread was still |
| 95 | running. |
| 96 | |
| Ned Deily | 3a2883c | 2019-06-12 23:31:45 -0400 | [diff] [blame] | 97 | |
| 98 | Optimizations |
| 99 | ============= |
| 100 | |
| 101 | |
| 102 | Build and C API Changes |
| 103 | ======================= |
| 104 | |
| 105 | |
| 106 | |
| 107 | Deprecated |
| 108 | ========== |
| 109 | |
| 110 | |
| 111 | |
| 112 | Removed |
| 113 | ======= |
| 114 | |
| 115 | |
| 116 | |
| 117 | Porting to Python 3.9 |
| 118 | ===================== |
| 119 | |
| 120 | This section lists previously described changes and other bugfixes |
| 121 | that may require changes to your code. |
| 122 | |
| 123 | |