"Zero cost" exception handling.
* Uses a lookup table to determine how to handle exceptions.
* Removes SETUP_FINALLY and POP_TOP block instructions, eliminating (most of) the runtime overhead of try statements.
* Reduces the size of the frame object by about 60%.
Modify the help in cpython/PC/launcher.c to show users that "latest" can be overridden by shebang, PY_PYTHON[n] or py.ini files. Also show that script [args] is optional by enclosing in square brackets.
Automerge-Triggered-By: @zooba
Break up COMPARE_OP into four logically distinct opcodes:
* COMPARE_OP for rich comparisons
* IS_OP for 'is' and 'is not' tests
* CONTAINS_OP for 'in' and 'is not' tests
* JUMP_IF_NOT_EXC_MATCH for checking exceptions in 'try-except' statements.
This commit contains the implementation of PEP570: Python positional-only parameters.
* Update Grammar/Grammar with new typedarglist and varargslist
* Regenerate grammar files
* Update and regenerate AST related files
* Update code object
* Update marshal.c
* Update compiler and symtable
* Regenerate importlib files
* Update callable objects
* Implement positional-only args logic in ceval.c
* Regenerate frozen data
* Update standard library to account for positional-only args
* Add test file for positional-only args
* Update other test files to account for positional-only args
* Add News entry
* Update inspect module and related tests
* bpo-30362 Add list options to launcher.
* bpo-30362 Add list options to help message.
* To avoid possible later conflict with python replaced flags with --launcher-list and --launcher-list-paths
* bpo-30362 Changed flag to -0 as suggested on review.
* bpo-30362: Modified to default to not path for -0, -0p to dispaly path and append * to default
* bpo-30362: Modified to display list on required version not found.
* bpo-30362 add --list and --list-paths added back in following review by paul.moore
* bpo-30362 Cleaner handing of -0 & -0p by not calling exit directly per review by @zooba
* bpo-30362: Tidy up and add news & what's new
Removed commented out line of code in PC/launcher.c.
Added the results of using blurb to add details of bpo-30362 & bpo-30291.
Updated Doc/whatsnew/3.7.rst to add a Windows only section covering both tickets.
* bpo-30362 Resolve conflict in Doc/whatsnew/3.7.rst
* bpo-30362:Address Whitespace Issue in Doc\whatsnew\3.7.rst
* Shorten NEWS message for bpo-30362
* Shorten NEWS item for bpo-30291
Special thanks to INADA Naoki for pushing the patch through
the last mile, Serhiy Storchaka for reviewing the code, and to
Victor Stinner for suggesting the idea (originally implemented
in the PyPy project).
The __class__ cell used by zero-argument super() is now initialized
from type.__new__ rather than __build_class__, so class methods
relying on that will now work correctly when called from metaclass
methods during class creation.
Patch by Martin Teichmann.
