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:mod:`ast` --- Abstract Syntax Trees
====================================
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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.. module:: ast
:synopsis: Abstract Syntax Tree classes and manipulation.
.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de>
.. sectionauthor:: Georg Brandl <georg@python.org>
**Source code:** :source:`Lib/ast.py`
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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2011-01-10 15:54:11 -04:00
--------------
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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The :mod:`ast` module helps Python applications to process trees of the Python
abstract syntax grammar. The abstract syntax itself might change with each
Python release; this module helps to find out programmatically what the current
grammar looks like.
An abstract syntax tree can be generated by passing :data:`ast.PyCF_ONLY_AST` as
a flag to the :func:`compile` built-in function, or using the :func:`parse`
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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helper provided in this module. The result will be a tree of objects whose
classes all inherit from :class:`ast.AST`. An abstract syntax tree can be
compiled into a Python code object using the built-in :func:`compile` function.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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Node classes
------------
.. class:: AST
This is the base of all AST node classes. The actual node classes are
derived from the :file:`Parser/Python.asdl` file, which is reproduced
:ref:`below <abstract-grammar>`. They are defined in the :mod:`_ast` C
module and re-exported in :mod:`ast`.
There is one class defined for each left-hand side symbol in the abstract
grammar (for example, :class:`ast.stmt` or :class:`ast.expr`). In addition,
there is one class defined for each constructor on the right-hand side; these
classes inherit from the classes for the left-hand side trees. For example,
:class:`ast.BinOp` inherits from :class:`ast.expr`. For production rules
with alternatives (aka "sums"), the left-hand side class is abstract: only
instances of specific constructor nodes are ever created.
.. index:: single: ? (question mark); in AST grammar
.. index:: single: * (asterisk); in AST grammar
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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.. attribute:: _fields
Each concrete class has an attribute :attr:`_fields` which gives the names
of all child nodes.
Each instance of a concrete class has one attribute for each child node,
of the type as defined in the grammar. For example, :class:`ast.BinOp`
instances have an attribute :attr:`left` of type :class:`ast.expr`.
If these attributes are marked as optional in the grammar (using a
question mark), the value might be ``None``. If the attributes can have
zero-or-more values (marked with an asterisk), the values are represented
as Python lists. All possible attributes must be present and have valid
values when compiling an AST with :func:`compile`.
.. attribute:: lineno
col_offset
bpo-33416: Add end positions to Python AST (GH-11605) The majority of this PR is tediously passing `end_lineno` and `end_col_offset` everywhere. Here are non-trivial points: * It is not possible to reconstruct end positions in AST "on the fly", some information is lost after an AST node is constructed, so we need two more attributes for every AST node `end_lineno` and `end_col_offset`. * I add end position information to both CST and AST. Although it may be technically possible to avoid adding end positions to CST, the code becomes more cumbersome and less efficient. * Since the end position is not known for non-leaf CST nodes while the next token is added, this requires a bit of extra care (see `_PyNode_FinalizeEndPos`). Unless I made some mistake, the algorithm should be linear. * For statements, I "trim" the end position of suites to not include the terminal newlines and dedent (this seems to be what people would expect), for example in ```python class C: pass pass ``` the end line and end column for the class definition is (2, 8). * For `end_col_offset` I use the common Python convention for indexing, for example for `pass` the `end_col_offset` is 4 (not 3), so that `[0:4]` gives one the source code that corresponds to the node. * I added a helper function `ast.get_source_segment()`, to get source text segment corresponding to a given AST node. It is also useful for testing. An (inevitable) downside of this PR is that AST now takes almost 25% more memory. I think however it is probably justified by the benefits.
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end_lineno
end_col_offset
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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Instances of :class:`ast.expr` and :class:`ast.stmt` subclasses have
bpo-33416: Add end positions to Python AST (GH-11605) The majority of this PR is tediously passing `end_lineno` and `end_col_offset` everywhere. Here are non-trivial points: * It is not possible to reconstruct end positions in AST "on the fly", some information is lost after an AST node is constructed, so we need two more attributes for every AST node `end_lineno` and `end_col_offset`. * I add end position information to both CST and AST. Although it may be technically possible to avoid adding end positions to CST, the code becomes more cumbersome and less efficient. * Since the end position is not known for non-leaf CST nodes while the next token is added, this requires a bit of extra care (see `_PyNode_FinalizeEndPos`). Unless I made some mistake, the algorithm should be linear. * For statements, I "trim" the end position of suites to not include the terminal newlines and dedent (this seems to be what people would expect), for example in ```python class C: pass pass ``` the end line and end column for the class definition is (2, 8). * For `end_col_offset` I use the common Python convention for indexing, for example for `pass` the `end_col_offset` is 4 (not 3), so that `[0:4]` gives one the source code that corresponds to the node. * I added a helper function `ast.get_source_segment()`, to get source text segment corresponding to a given AST node. It is also useful for testing. An (inevitable) downside of this PR is that AST now takes almost 25% more memory. I think however it is probably justified by the benefits.
2019-01-22 07:18:22 -04:00
:attr:`lineno`, :attr:`col_offset`, :attr:`lineno`, and :attr:`col_offset`
attributes. The :attr:`lineno` and :attr:`end_lineno` are the first and
last line numbers of source text span (1-indexed so the first line is line 1)
and the :attr:`col_offset` and :attr:`end_col_offset` are the corresponding
UTF-8 byte offsets of the first and last tokens that generated the node.
The UTF-8 offset is recorded because the parser uses UTF-8 internally.
Note that the end positions are not required by the compiler and are
therefore optional. The end offset is *after* the last symbol, for example
one can get the source segment of a one-line expression node using
``source_line[node.col_offset : node.end_col_offset]``.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
The constructor of a class :class:`ast.T` parses its arguments as follows:
* If there are positional arguments, there must be as many as there are items
in :attr:`T._fields`; they will be assigned as attributes of these names.
* If there are keyword arguments, they will set the attributes of the same
names to the given values.
For example, to create and populate an :class:`ast.UnaryOp` node, you could
use ::
node = ast.UnaryOp()
node.op = ast.USub()
node.operand = ast.Constant()
node.operand.value = 5
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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node.operand.lineno = 0
node.operand.col_offset = 0
node.lineno = 0
node.col_offset = 0
or the more compact ::
node = ast.UnaryOp(ast.USub(), ast.Constant(5, lineno=0, col_offset=0),
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
lineno=0, col_offset=0)
.. deprecated:: 3.8
Class :class:`ast.Constant` is now used for all constants. Old classes
:class:`ast.Num`, :class:`ast.Str`, :class:`ast.Bytes`,
:class:`ast.NameConstant` and :class:`ast.Ellipsis` are still available,
but they will be removed in future Python releases.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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.. _abstract-grammar:
Abstract Grammar
----------------
The abstract grammar is currently defined as follows:
.. literalinclude:: ../../Parser/Python.asdl
:language: none
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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:mod:`ast` Helpers
------------------
Apart from the node classes, the :mod:`ast` module defines these utility functions
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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and classes for traversing abstract syntax trees:
.. function:: parse(source, filename='<unknown>', mode='exec', *, type_comments=False, feature_version=-1)
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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Parse the source into an AST node. Equivalent to ``compile(source,
filename, mode, ast.PyCF_ONLY_AST)``.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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If ``type_comments=True`` is given, the parser is modified to check
and return type comments as specified by :pep:`484` and :pep:`526`.
This is equivalent to adding :data:`ast.PyCF_TYPE_COMMENTS` to the
flags passed to :func:`compile()`. This will report syntax errors
for misplaced type comments. Without this flag, type comments will
be ignored, and the ``type_comment`` field on selected AST nodes
will always be ``None``. In addition, the locations of ``# type:
ignore`` comments will be returned as the ``type_ignores``
attribute of :class:`Module` (otherwise it is always an empty list).
In addition, if ``mode`` is ``'func_type'``, the input syntax is
modified to correspond to :pep:`484` "signature type comments",
e.g. ``(str, int) -> List[str]``.
Also, setting ``feature_version`` to the minor version of an
earlier Python 3 version will attempt to parse using that version's
grammar. For example, setting ``feature_version=4`` will allow
the use of ``async`` and ``await`` as variable names. The lowest
supported value is 4; the highest is ``sys.version_info[1]``.
.. warning::
It is possible to crash the Python interpreter with a
sufficiently large/complex string due to stack depth limitations
in Python's AST compiler.
.. versionchanged:: 3.8
Added ``type_comments``, ``mode='func_type'`` and ``feature_version``.
2009-01-03 17:18:54 -04:00
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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.. function:: literal_eval(node_or_string)
Safely evaluate an expression node or a string containing a Python literal or
container display. The string or node provided may only consist of the
following Python literal structures: strings, bytes, numbers, tuples, lists,
dicts, sets, booleans, and ``None``.
This can be used for safely evaluating strings containing Python values from
untrusted sources without the need to parse the values oneself. It is not
capable of evaluating arbitrarily complex expressions, for example involving
operators or indexing.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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.. warning::
It is possible to crash the Python interpreter with a
sufficiently large/complex string due to stack depth limitations
in Python's AST compiler.
2010-07-11 06:41:21 -03:00
.. versionchanged:: 3.2
2010-07-13 03:38:10 -03:00
Now allows bytes and set literals.
2010-07-11 06:41:21 -03:00
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
Merged revisions 64089,64098,64100-64102,64113,64115-64116,64118,64120,64132,64342 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r64089 | armin.ronacher | 2008-06-10 22:37:02 +0200 (mar., 10 juin 2008) | 3 lines Fix a formatting error in the ast documentation. ........ r64098 | raymond.hettinger | 2008-06-11 02:25:29 +0200 (mer., 11 juin 2008) | 6 lines Mini-PEP: Simplifying numbers.py * Convert binary methods in Integral to mixin methods * Remove three-arg __pow__ as a required method * Make __int__ the root method instead of __long__. ........ r64100 | raymond.hettinger | 2008-06-11 02:28:51 +0200 (mer., 11 juin 2008) | 1 line Update numbers doc for the Integral simplification. ........ r64101 | raymond.hettinger | 2008-06-11 02:44:47 +0200 (mer., 11 juin 2008) | 3 lines Handle the case with zero arguments. ........ r64102 | benjamin.peterson | 2008-06-11 03:31:28 +0200 (mer., 11 juin 2008) | 4 lines convert test_struct to a unittest thanks to Giampaolo Rodola I had to disable one test because it was functioning incorrectly, see #1530559 I also removed the debugging prints ........ r64113 | thomas.heller | 2008-06-11 09:10:43 +0200 (mer., 11 juin 2008) | 2 lines Fix markup. Document the new 'offset' parameter for the 'ctypes.byref' function. ........ r64115 | raymond.hettinger | 2008-06-11 12:30:54 +0200 (mer., 11 juin 2008) | 1 line Multi-arg form for set.difference() and set.difference_update(). ........ r64116 | raymond.hettinger | 2008-06-11 14:06:49 +0200 (mer., 11 juin 2008) | 1 line Issue 3051: Let heapq work with either __lt__ or __le__. ........ r64118 | raymond.hettinger | 2008-06-11 14:39:09 +0200 (mer., 11 juin 2008) | 1 line Optimize previous checkin for heapq. ........ r64120 | raymond.hettinger | 2008-06-11 15:14:50 +0200 (mer., 11 juin 2008) | 1 line Add test for heapq using both __lt__ and __le__. ........ r64132 | gregory.p.smith | 2008-06-11 20:00:52 +0200 (mer., 11 juin 2008) | 3 lines Correct an incorrect comment about our #include of stddef.h. (see Doug Evans' comment on python-dev 2008-06-10) ........ r64342 | guido.van.rossum | 2008-06-17 19:38:02 +0200 (mar., 17 juin 2008) | 3 lines Roll back Raymond's -r64098 while we think of something better. (See issue 3056 -- we're close to a resolution but need unittests.) ........
2008-06-17 17:36:03 -03:00
.. function:: get_docstring(node, clean=True)
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
Return the docstring of the given *node* (which must be a
:class:`FunctionDef`, :class:`AsyncFunctionDef`, :class:`ClassDef`,
or :class:`Module` node), or ``None`` if it has no docstring.
If *clean* is true, clean up the docstring's indentation with
:func:`inspect.cleandoc`.
.. versionchanged:: 3.5
:class:`AsyncFunctionDef` is now supported.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
bpo-33416: Add end positions to Python AST (GH-11605) The majority of this PR is tediously passing `end_lineno` and `end_col_offset` everywhere. Here are non-trivial points: * It is not possible to reconstruct end positions in AST "on the fly", some information is lost after an AST node is constructed, so we need two more attributes for every AST node `end_lineno` and `end_col_offset`. * I add end position information to both CST and AST. Although it may be technically possible to avoid adding end positions to CST, the code becomes more cumbersome and less efficient. * Since the end position is not known for non-leaf CST nodes while the next token is added, this requires a bit of extra care (see `_PyNode_FinalizeEndPos`). Unless I made some mistake, the algorithm should be linear. * For statements, I "trim" the end position of suites to not include the terminal newlines and dedent (this seems to be what people would expect), for example in ```python class C: pass pass ``` the end line and end column for the class definition is (2, 8). * For `end_col_offset` I use the common Python convention for indexing, for example for `pass` the `end_col_offset` is 4 (not 3), so that `[0:4]` gives one the source code that corresponds to the node. * I added a helper function `ast.get_source_segment()`, to get source text segment corresponding to a given AST node. It is also useful for testing. An (inevitable) downside of this PR is that AST now takes almost 25% more memory. I think however it is probably justified by the benefits.
2019-01-22 07:18:22 -04:00
.. function:: get_source_segment(source, node, *, padded=False)
Get source code segment of the *source* that generated *node*.
If some location information (:attr:`lineno`, :attr:`end_lineno`,
:attr:`col_offset`, or :attr:`end_col_offset`) is missing, return ``None``.
If *padded* is ``True``, the first line of a multi-line statement will
be padded with spaces to match its original position.
.. versionadded:: 3.8
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
.. function:: fix_missing_locations(node)
When you compile a node tree with :func:`compile`, the compiler expects
:attr:`lineno` and :attr:`col_offset` attributes for every node that supports
them. This is rather tedious to fill in for generated nodes, so this helper
adds these attributes recursively where not already set, by setting them to
the values of the parent node. It works recursively starting at *node*.
.. function:: increment_lineno(node, n=1)
bpo-33416: Add end positions to Python AST (GH-11605) The majority of this PR is tediously passing `end_lineno` and `end_col_offset` everywhere. Here are non-trivial points: * It is not possible to reconstruct end positions in AST "on the fly", some information is lost after an AST node is constructed, so we need two more attributes for every AST node `end_lineno` and `end_col_offset`. * I add end position information to both CST and AST. Although it may be technically possible to avoid adding end positions to CST, the code becomes more cumbersome and less efficient. * Since the end position is not known for non-leaf CST nodes while the next token is added, this requires a bit of extra care (see `_PyNode_FinalizeEndPos`). Unless I made some mistake, the algorithm should be linear. * For statements, I "trim" the end position of suites to not include the terminal newlines and dedent (this seems to be what people would expect), for example in ```python class C: pass pass ``` the end line and end column for the class definition is (2, 8). * For `end_col_offset` I use the common Python convention for indexing, for example for `pass` the `end_col_offset` is 4 (not 3), so that `[0:4]` gives one the source code that corresponds to the node. * I added a helper function `ast.get_source_segment()`, to get source text segment corresponding to a given AST node. It is also useful for testing. An (inevitable) downside of this PR is that AST now takes almost 25% more memory. I think however it is probably justified by the benefits.
2019-01-22 07:18:22 -04:00
Increment the line number and end line number of each node in the tree
starting at *node* by *n*. This is useful to "move code" to a different
location in a file.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
.. function:: copy_location(new_node, old_node)
bpo-33416: Add end positions to Python AST (GH-11605) The majority of this PR is tediously passing `end_lineno` and `end_col_offset` everywhere. Here are non-trivial points: * It is not possible to reconstruct end positions in AST "on the fly", some information is lost after an AST node is constructed, so we need two more attributes for every AST node `end_lineno` and `end_col_offset`. * I add end position information to both CST and AST. Although it may be technically possible to avoid adding end positions to CST, the code becomes more cumbersome and less efficient. * Since the end position is not known for non-leaf CST nodes while the next token is added, this requires a bit of extra care (see `_PyNode_FinalizeEndPos`). Unless I made some mistake, the algorithm should be linear. * For statements, I "trim" the end position of suites to not include the terminal newlines and dedent (this seems to be what people would expect), for example in ```python class C: pass pass ``` the end line and end column for the class definition is (2, 8). * For `end_col_offset` I use the common Python convention for indexing, for example for `pass` the `end_col_offset` is 4 (not 3), so that `[0:4]` gives one the source code that corresponds to the node. * I added a helper function `ast.get_source_segment()`, to get source text segment corresponding to a given AST node. It is also useful for testing. An (inevitable) downside of this PR is that AST now takes almost 25% more memory. I think however it is probably justified by the benefits.
2019-01-22 07:18:22 -04:00
Copy source location (:attr:`lineno`, :attr:`col_offset`, :attr:`end_lineno`,
and :attr:`end_col_offset`) from *old_node* to *new_node* if possible,
and return *new_node*.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
.. function:: iter_fields(node)
Yield a tuple of ``(fieldname, value)`` for each field in ``node._fields``
that is present on *node*.
.. function:: iter_child_nodes(node)
Yield all direct child nodes of *node*, that is, all fields that are nodes
and all items of fields that are lists of nodes.
.. function:: walk(node)
Recursively yield all descendant nodes in the tree starting at *node*
(including *node* itself), in no specified order. This is useful if you only
want to modify nodes in place and don't care about the context.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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.. class:: NodeVisitor()
A node visitor base class that walks the abstract syntax tree and calls a
visitor function for every node found. This function may return a value
which is forwarded by the :meth:`visit` method.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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This class is meant to be subclassed, with the subclass adding visitor
methods.
.. method:: visit(node)
Visit a node. The default implementation calls the method called
:samp:`self.visit_{classname}` where *classname* is the name of the node
class, or :meth:`generic_visit` if that method doesn't exist.
.. method:: generic_visit(node)
This visitor calls :meth:`visit` on all children of the node.
2009-01-03 17:18:54 -04:00
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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Note that child nodes of nodes that have a custom visitor method won't be
visited unless the visitor calls :meth:`generic_visit` or visits them
itself.
Don't use the :class:`NodeVisitor` if you want to apply changes to nodes
during traversal. For this a special visitor exists
(:class:`NodeTransformer`) that allows modifications.
.. class:: NodeTransformer()
A :class:`NodeVisitor` subclass that walks the abstract syntax tree and
allows modification of nodes.
The :class:`NodeTransformer` will walk the AST and use the return value of
the visitor methods to replace or remove the old node. If the return value
of the visitor method is ``None``, the node will be removed from its
location, otherwise it is replaced with the return value. The return value
may be the original node in which case no replacement takes place.
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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Here is an example transformer that rewrites all occurrences of name lookups
(``foo``) to ``data['foo']``::
class RewriteName(NodeTransformer):
def visit_Name(self, node):
return copy_location(Subscript(
value=Name(id='data', ctx=Load()),
slice=Index(value=Constant(value=node.id)),
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
2008-06-10 13:37:50 -03:00
ctx=node.ctx
), node)
Keep in mind that if the node you're operating on has child nodes you must
either transform the child nodes yourself or call the :meth:`generic_visit`
method for the node first.
For nodes that were part of a collection of statements (that applies to all
statement nodes), the visitor may also return a list of nodes rather than
just a single node.
Usually you use the transformer like this::
node = YourTransformer().visit(node)
.. function:: dump(node, annotate_fields=True, include_attributes=False)
Return a formatted dump of the tree in *node*. This is mainly useful for
debugging purposes. The returned string will show the names and the values
for fields. This makes the code impossible to evaluate, so if evaluation is
wanted *annotate_fields* must be set to ``False``. Attributes such as line
Merged revisions 64434-64435,64440-64443,64445,64447-64448,64450,64452,64455,64461,64464,64466,64468 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r64434 | andrew.kuchling | 2008-06-20 18:13:58 -0500 (Fri, 20 Jun 2008) | 1 line Remove request for e-mail; it's unlikely these classes will be saved ........ r64435 | andrew.kuchling | 2008-06-20 18:14:32 -0500 (Fri, 20 Jun 2008) | 1 line Grammar fixes ........ r64440 | andrew.kuchling | 2008-06-21 08:29:12 -0500 (Sat, 21 Jun 2008) | 1 line Docstring typo ........ r64441 | andrew.kuchling | 2008-06-21 08:47:20 -0500 (Sat, 21 Jun 2008) | 1 line Use repr() for bad input strings; this makes the empty string or binary characters more visible ........ r64442 | andrew.kuchling | 2008-06-21 08:48:38 -0500 (Sat, 21 Jun 2008) | 1 line Docstring correction ........ r64443 | georg.brandl | 2008-06-21 09:26:19 -0500 (Sat, 21 Jun 2008) | 2 lines Documentation fix. ........ r64445 | facundo.batista | 2008-06-21 12:30:06 -0500 (Sat, 21 Jun 2008) | 3 lines Reviewed and updated the documentation. Fixes #3017. ........ r64447 | facundo.batista | 2008-06-21 13:58:04 -0500 (Sat, 21 Jun 2008) | 6 lines Now a from submitted via POST that also has a query string will contain both FieldStorage and MiniFieldStorage items. Fixes #1817. ........ r64448 | facundo.batista | 2008-06-21 14:48:19 -0500 (Sat, 21 Jun 2008) | 5 lines In the deprecated functions I added an alert to review specially a section of the subprocess documentation that helps with the replacing of those functionss. ........ r64450 | georg.brandl | 2008-06-22 04:05:29 -0500 (Sun, 22 Jun 2008) | 2 lines Turn section references into proper cross-references. ........ r64452 | facundo.batista | 2008-06-22 08:36:20 -0500 (Sun, 22 Jun 2008) | 5 lines Issue #2722. Now the char buffer to support the path string has not fixed length, it mallocs memory if needed. As a result, we don't have a maximum for the getcwd() method. ........ r64455 | facundo.batista | 2008-06-22 10:27:10 -0500 (Sun, 22 Jun 2008) | 4 lines Issue 3164. Small fix to don't repeat a comparation without necessity. ........ r64461 | georg.brandl | 2008-06-22 13:11:52 -0500 (Sun, 22 Jun 2008) | 2 lines #3085: Fix syntax error. ........ r64464 | georg.brandl | 2008-06-22 13:31:54 -0500 (Sun, 22 Jun 2008) | 2 lines Expand docstrings of sqlite3 functions. ........ r64466 | georg.brandl | 2008-06-22 14:07:59 -0500 (Sun, 22 Jun 2008) | 2 lines Write out "phi" consistently. ........ r64468 | facundo.batista | 2008-06-22 14:35:24 -0500 (Sun, 22 Jun 2008) | 4 lines Just returning nothing instead of rising TestSkipped, because it makes the test fail in the trunk.loewis-sun buildbot. ........
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numbers and column offsets are not dumped by default. If this is wanted,
Merged revisions 63829-63831,63858,63865,63879,63882,63948,63970-63972,63976,63989,64014-64015,64021-64022,64063-64065,64067 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r63829 | mark.summerfield | 2008-05-31 15:05:34 +0200 (Sat, 31 May 2008) | 4 lines Added a note to [] that special forms & special chars lose their meaning and backrefs can't be used inside [] ........ r63830 | georg.brandl | 2008-05-31 16:40:09 +0200 (Sat, 31 May 2008) | 2 lines #3010: clarification about stdin/use_rawinput. ........ r63831 | georg.brandl | 2008-05-31 16:45:55 +0200 (Sat, 31 May 2008) | 2 lines #3005: add explaining sentence to easydialogs docs. ........ r63858 | georg.brandl | 2008-06-01 18:41:31 +0200 (Sun, 01 Jun 2008) | 2 lines Add plain text make target. ........ r63865 | georg.brandl | 2008-06-01 21:24:36 +0200 (Sun, 01 Jun 2008) | 2 lines Spaces vs. tabs. ........ r63879 | gregory.p.smith | 2008-06-02 00:57:47 +0200 (Mon, 02 Jun 2008) | 3 lines Make the _H #define's match the header file names. Fix comments to mention the correct type names. ........ r63882 | gregory.p.smith | 2008-06-02 01:48:47 +0200 (Mon, 02 Jun 2008) | 3 lines Adds a Thread.getIdent() method to provide the _get_ident() value for any given threading.Thread object. feature request issue 2871. ........ r63948 | alexandre.vassalotti | 2008-06-04 22:41:44 +0200 (Wed, 04 Jun 2008) | 2 lines Fixed complex.__getnewargs__() to not emit another complex object. ........ r63970 | andrew.kuchling | 2008-06-06 01:33:54 +0200 (Fri, 06 Jun 2008) | 1 line Document 'utc' parameter ........ r63971 | andrew.kuchling | 2008-06-06 01:35:31 +0200 (Fri, 06 Jun 2008) | 1 line Add various items ........ r63972 | andrew.kuchling | 2008-06-06 01:35:48 +0200 (Fri, 06 Jun 2008) | 1 line Grammar fix ........ r63976 | georg.brandl | 2008-06-06 09:34:50 +0200 (Fri, 06 Jun 2008) | 2 lines Markup fix. ........ r63989 | thomas.heller | 2008-06-06 20:42:11 +0200 (Fri, 06 Jun 2008) | 2 lines Add a reminder for the maintainer of whatsnew. ........ r64014 | georg.brandl | 2008-06-07 17:59:10 +0200 (Sat, 07 Jun 2008) | 3 lines Factor out docstring dedenting from inspect.getdoc() into inspect.cleandoc() to ease standalone use of the algorithm. ........ r64015 | georg.brandl | 2008-06-07 18:04:01 +0200 (Sat, 07 Jun 2008) | 2 lines Revert unwanted changes. ........ r64021 | georg.brandl | 2008-06-07 20:16:12 +0200 (Sat, 07 Jun 2008) | 2 lines X-ref to numbers module. ........ r64022 | georg.brandl | 2008-06-07 20:17:37 +0200 (Sat, 07 Jun 2008) | 3 lines Document the "st" API, to avoid confusion with the "new" AST. Add a note about using the new AST module. ........ r64063 | martin.v.loewis | 2008-06-10 07:03:35 +0200 (Tue, 10 Jun 2008) | 2 lines Add Gregor Lingl. ........ r64064 | georg.brandl | 2008-06-10 09:45:28 +0200 (Tue, 10 Jun 2008) | 2 lines Add the "ast" module, containing helpers to ease use of the "_ast" classes. ........ r64065 | raymond.hettinger | 2008-06-10 09:57:15 +0200 (Tue, 10 Jun 2008) | 1 line Add Arnaud for his efforts on multi-arg set operations. ........ r64067 | georg.brandl | 2008-06-10 14:46:39 +0200 (Tue, 10 Jun 2008) | 2 lines #2536: fix itertools.permutations and itertools.combinations docstrings. ........
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*include_attributes* can be set to ``True``.
.. seealso::
`Green Tree Snakes <https://greentreesnakes.readthedocs.io/>`_, an external documentation resource, has good
details on working with Python ASTs.