Add initial docs.

Author: ericsnowcurrently

Doc/library/concurrency.rst

@@ -23,6 +23,8 @@ multitasking). Here's an overview:
    queue.rst
    contextvars.rst
 
+Also see the :mod:`interpreters` module.
+
 
 The following are support modules for some of the above services:
 

Doc/library/interpreters.rst

@@ -0,0 +1,160 @@
+:mod:`!interpreters` --- Multiple Interpreters in the Same Process
+==================================================================
+
+.. module:: interpreters
+   :synopsis: Multiple Interpreters in the Same Process
+
+.. moduleauthor:: Eric Snow <[email protected]>
+.. sectionauthor:: Eric Snow <[email protected]>
+
+.. versionadded:: 3.14
+
+**Source code:** :source:`Lib/interpreters/__init__.py`
+
+--------------
+
+
+Introduction
+------------
+
+The :mod:`!interpreters` module constructs higher-level interfaces
+on top of the lower level :mod:`!_interpreters` module.
+
+.. XXX Add references to the upcoming HOWTO docs in the seealso block.
+
+.. seealso::
+
+   :ref:`isolating-extensions-howto`
+       how to update an extension module to support multiple interpreters
+
+   :pep:`554`
+
+   :pep:`734`
+
+   :pep:`684`
+
+.. XXX Why do we disallow multiple interpreters on WASM?
+
+.. include:: ../includes/wasm-notavail.rst
+
+
+Key Details
+-----------
+
+Before we dive into examples, there are a small number of details
+to keep in mind about using multiple interpreters:
+
+* isolated, by default
+* no implicit threads
+* not all PyPI packages support use in multiple interpreters yet
+
+.. XXX Are there other relevant details to list?
+
+
+API Summary
+-----------
+
++----------------------------------+----------------------------------------------+
+| signature                        | description                                  |
++==================================+==============================================+
+| ``list_all() -> [Interpreter]``  | Get all existing interpreters.               |
++----------------------------------+----------------------------------------------+
+| ``get_current() -> Interpreter`` | Get the currently running interpreter.       |
++----------------------------------+----------------------------------------------+
+| ``get_main() -> Interpreter``    | Get the main interpreter.                    |
++----------------------------------+----------------------------------------------+
+| ``create() -> Interpreter``      | Initialize a new (idle) Python interpreter.  |
++----------------------------------+----------------------------------------------+
+
+|
+
++---------------------------------------------------+---------------------------------------------------+
+| signature                                         | description                                       |
++===================================================+===================================================+
+| ``class Interpreter``                             | A single interpreter.                             |
++---------------------------------------------------+---------------------------------------------------+
+| ``.id``                                           | The interpreter's ID (read-only).                 |
++---------------------------------------------------+---------------------------------------------------+
+| ``.whence``                                       | Where the interpreter came from (read-only).      |
++---------------------------------------------------+---------------------------------------------------+
+| ``.is_running() -> bool``                         | Is the interpreter currently executing code       |
+|                                                   | in its :mod:`!__main__` module?                   |
++---------------------------------------------------+---------------------------------------------------+
+| ``.close()``                                      | Finalize and destroy the interpreter.             |
++---------------------------------------------------+---------------------------------------------------+
+| ``.prepare_main(ns=None, **kwargs)``              | Bind "shareable" objects in :mod:`!__main__`.     |
++---------------------------------------------------+---------------------------------------------------+
+| ``.exec(src_str, /, dedent=True)``                | | Run the given source code in the interpreter    |
+|                                                   | | (in the current thread).                        |
++---------------------------------------------------+---------------------------------------------------+
+| ``.call(callable, /, *args, **kwargs)``           | | Run the given function in the interpreter       |
+|                                                   | | (in the current thread).                        |
++---------------------------------------------------+---------------------------------------------------+
+| ``.call_in_thread(callable, /, *args, **kwargs)`` | | Run the given function in the interpreter       |
+|                                                   | | (in a new thread).                              |
++---------------------------------------------------+---------------------------------------------------+
+
+Exceptions:
+
++--------------------------+------------------+---------------------------------------------------+
+| class                    | base class       | description                                       |
++==========================+==================+===================================================+
+| InterpreterError         | Exception        | An interpreter-related error happened.            |
++--------------------------+------------------+---------------------------------------------------+
+| InterpreterNotFoundError | InterpreterError | The targeted interpreter no longer exists.        |
++--------------------------+------------------+---------------------------------------------------+
+| ExecutionFailed          | InterpreterError | The running code raised an uncaught exception.    |
++--------------------------+------------------+---------------------------------------------------+
+| NotShareableError        | TypeError        | The object cannot be sent to another interpreter. |
++--------------------------+------------------+---------------------------------------------------+
+
+.. XXX Document the ExecutionFailed attrs.
+
+
+.. XXX Add API summary for communicating between interpreters.
+
+
+.. _interp-examples:
+
+Basic Usage
+-----------
+
+Creating an interpreter and running code in it:
+
+::
+
+    import interpreters
+
+    interp = interpreters.create()
+
+    # Run in the current OS thread.
+
+    interp.exec('print("spam!")')
+
+    interp.exec("""if True:
+        print('spam!')
+        """)
+
+    from textwrap import dedent
+    interp.exec(dedent("""
+        print('spam!')
+        """))
+
+    def run():
+        print('spam!')
+
+    interp.call(run)
+
+    # Run in new OS thread.
+
+    t = interp.call_in_thread(run)
+    t.join()
+
+
+.. XXX Describe module functions in more detail.
+
+
+.. XXX Describe module types in more detail.
+
+
+.. XXX Explain about object "sharing".

Doc/library/python.rst

@@ -17,6 +17,7 @@ overview:
    builtins.rst
    __main__.rst
    warnings.rst
+   interpreters.rst
    dataclasses.rst
    contextlib.rst
    abc.rst