diff options
| -rw-r--r-- | Doc/c-api/unicode.rst | 4 | ||||
| -rw-r--r-- | Doc/c-api/veryhigh.rst | 20 | ||||
| -rw-r--r-- | Doc/faq/windows.rst | 22 | ||||
| -rw-r--r-- | Doc/library/argparse.rst | 65 | ||||
| -rw-r--r-- | Doc/library/base64.rst | 1 | ||||
| -rw-r--r-- | Doc/library/dis.rst | 2 | ||||
| -rw-r--r-- | Doc/library/hmac.rst | 4 | ||||
| -rw-r--r-- | Doc/library/os.rst | 6 | ||||
| -rw-r--r-- | Doc/library/parser.rst | 337 | ||||
| -rw-r--r-- | Doc/library/pickle.rst | 12 | ||||
| -rw-r--r-- | Doc/library/stdtypes.rst | 13 | ||||
| -rw-r--r-- | Doc/library/sys.rst | 39 | ||||
| -rw-r--r-- | Doc/tutorial/classes.rst | 35 |
13 files changed, 127 insertions, 433 deletions
diff --git a/Doc/c-api/unicode.rst b/Doc/c-api/unicode.rst index fc9368d7ed..964d2c86bd 100644 --- a/Doc/c-api/unicode.rst +++ b/Doc/c-api/unicode.rst @@ -208,7 +208,7 @@ APIs: .. cfunction:: PyObject* PyUnicode_FromUnicode(const Py_UNICODE *u, Py_ssize_t size) - Create a Unicode Object from the Py_UNICODE buffer *u* of the given size. *u* + Create a Unicode object from the Py_UNICODE buffer *u* of the given size. *u* may be *NULL* which causes the contents to be undefined. It is the user's responsibility to fill in the needed data. The buffer is copied into the new object. If the buffer is not *NULL*, the return value might be a shared object. @@ -222,7 +222,7 @@ APIs: .. cfunction:: PyObject* PyUnicode_FromStringAndSize(const char *u, Py_ssize_t size) - Create a Unicode Object from the char buffer *u*. The bytes will be interpreted + Create a Unicode object from the char buffer *u*. The bytes will be interpreted as being UTF-8 encoded. *u* may also be *NULL* which causes the contents to be undefined. It is the user's responsibility to fill in the needed data. The buffer is copied into the new object. If the buffer is not diff --git a/Doc/c-api/veryhigh.rst b/Doc/c-api/veryhigh.rst index 1ca11cbce0..23f7c852db 100644 --- a/Doc/c-api/veryhigh.rst +++ b/Doc/c-api/veryhigh.rst @@ -121,13 +121,13 @@ the same library that the Python runtime is using. .. cfunction:: int PyRun_InteractiveOneFlags(FILE *fp, const char *filename, PyCompilerFlags *flags) - Read and execute a single statement from a file associated with an interactive - device according to the *flags* argument. If *filename* is *NULL*, ``"???"`` is - used instead. The user will be prompted using ``sys.ps1`` and ``sys.ps2``. - Returns ``0`` when the input was executed successfully, ``-1`` if there was an - exception, or an error code from the :file:`errcode.h` include file distributed - as part of Python if there was a parse error. (Note that :file:`errcode.h` is - not included by :file:`Python.h`, so must be included specifically if needed.) + Read and execute a single statement from a file associated with an + interactive device according to the *flags* argument. The user will be + prompted using ``sys.ps1`` and ``sys.ps2``. Returns ``0`` when the input was + executed successfully, ``-1`` if there was an exception, or an error code + from the :file:`errcode.h` include file distributed as part of Python if + there was a parse error. (Note that :file:`errcode.h` is not included by + :file:`Python.h`, so must be included specifically if needed.) .. cfunction:: int PyRun_InteractiveLoop(FILE *fp, const char *filename) @@ -136,11 +136,11 @@ the same library that the Python runtime is using. leaving *flags* set to *NULL*. -.. cfunction:: int PyRun_InteractiveLoopFlags(FILE *fp, const char *filename, PyCompilerFlags *flags) +.. cfunction:: int PyRun_InteractiveLoopFlags(FILE *fp, const char *filename, PyCompilerFlags *flags) Read and execute statements from a file associated with an interactive device - until EOF is reached. If *filename* is *NULL*, ``"???"`` is used instead. The - user will be prompted using ``sys.ps1`` and ``sys.ps2``. Returns ``0`` at EOF. + until EOF is reached. The user will be prompted using ``sys.ps1`` and + ``sys.ps2``. Returns ``0`` at EOF. .. cfunction:: struct _node* PyParser_SimpleParseString(const char *str, int start) diff --git a/Doc/faq/windows.rst b/Doc/faq/windows.rst index a1dec3a7fe..47c09ad014 100644 --- a/Doc/faq/windows.rst +++ b/Doc/faq/windows.rst @@ -286,20 +286,18 @@ Embedding the Python interpreter in a Windows app can be summarized as follows: 1. Do _not_ build Python into your .exe file directly. On Windows, Python must be a DLL to handle importing modules that are themselves DLL's. (This is the - first key undocumented fact.) Instead, link to :file:`python{NN}.dll`; it is - typically installed in ``C:\Windows\System``. NN is the Python version, a + first key undocumented fact.) Instead, link to :file:`python{NN}.dll`; it is + typically installed in ``C:\Windows\System``. *NN* is the Python version, a number such as "23" for Python 2.3. - You can link to Python statically or dynamically. Linking statically means - linking against :file:`python{NN}.lib`, while dynamically linking means - linking against :file:`python{NN}.dll`. The drawback to dynamic linking is - that your app won't run if :file:`python{NN}.dll` does not exist on your - system. (General note: :file:`python{NN}.lib` is the so-called "import lib" - corresponding to :file:`python.dll`. It merely defines symbols for the - linker.) + You can link to Python in two different ways. Load-time linking means + linking against :file:`python{NN}.lib`, while run-time linking means linking + against :file:`python{NN}.dll`. (General note: :file:`python{NN}.lib` is the + so-called "import lib" corresponding to :file:`python{NN}.dll`. It merely + defines symbols for the linker.) - Linking dynamically greatly simplifies link options; everything happens at - run time. Your code must load :file:`python{NN}.dll` using the Windows + Run-time linking greatly simplifies link options; everything happens at run + time. Your code must load :file:`python{NN}.dll` using the Windows ``LoadLibraryEx()`` routine. The code must also use access routines and data in :file:`python{NN}.dll` (that is, Python's C API's) using pointers obtained by the Windows ``GetProcAddress()`` routine. Macros can make using these @@ -308,6 +306,8 @@ Embedding the Python interpreter in a Windows app can be summarized as follows: Borland note: convert :file:`python{NN}.lib` to OMF format using Coff2Omf.exe first. + .. XXX what about static linking? + 2. If you use SWIG, it is easy to create a Python "extension module" that will make the app's data and methods available to Python. SWIG will handle just about all the grungy details for you. The result is C code that you link diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst index 6bd011bea3..0ea8195a0e 100644 --- a/Doc/library/argparse.rst +++ b/Doc/library/argparse.rst @@ -1,5 +1,5 @@ -:mod:`argparse` -- Parser for command line options, arguments and sub-commands -============================================================================== +:mod:`argparse` --- Parser for command line options, arguments and sub-commands +=============================================================================== .. module:: argparse :synopsis: Command-line option and argument parsing library. @@ -14,6 +14,7 @@ will figure out how to parse those out of :data:`sys.argv`. The :mod:`argparse` module also automatically generates help and usage messages and issues errors when users give the program invalid arguments. + Example ------- @@ -64,6 +65,7 @@ If invalid arguments are passed in, it will issue an error:: The following sections walk you through this example. + Creating a parser ^^^^^^^^^^^^^^^^^ @@ -97,6 +99,7 @@ will be a list of one or more ints, and the ``accumulate`` attribute will be either the :func:`sum` function, if ``--sum`` was specified at the command line, or the :func:`max` function if it was not. + Parsing arguments ^^^^^^^^^^^^^^^^^ @@ -248,7 +251,6 @@ the help options:: +h, ++help show this help message and exit - prefix_chars ^^^^^^^^^^^^ @@ -295,6 +297,7 @@ equivalent to the expression ``['-f', 'foo', '-f', 'bar']``. The ``fromfile_prefix_chars=`` argument defaults to ``None``, meaning that arguments will never be treated as file references. + argument_default ^^^^^^^^^^^^^^^^ @@ -594,6 +597,7 @@ The add_argument() method The following sections describe how each of these are used. + name or flags ^^^^^^^^^^^^^ @@ -623,6 +627,7 @@ When :meth:`parse_args` is called, optional arguments will be identified by the usage: PROG [-h] [-f FOO] bar PROG: error: too few arguments + action ^^^^^^ @@ -767,8 +772,10 @@ values are: output files:: >>> parser = argparse.ArgumentParser() - >>> parser.add_argument('infile', nargs='?', type=argparse.FileType('r'), default=sys.stdin) - >>> parser.add_argument('outfile', nargs='?', type=argparse.FileType('w'), default=sys.stdout) + >>> parser.add_argument('infile', nargs='?', type=argparse.FileType('r'), + ... default=sys.stdin) + >>> parser.add_argument('outfile', nargs='?', type=argparse.FileType('w'), + ... default=sys.stdout) >>> parser.parse_args(['input.txt', 'output.txt']) Namespace(infile=<open file 'input.txt', mode 'r' at 0x...>, outfile=<open file 'output.txt', mode 'w' at 0x...>) >>> parser.parse_args([]) @@ -1128,7 +1135,7 @@ behavior:: The parse_args() method ----------------------- -.. method:: ArgumentParser.parse_args([args], [namespace]) +.. method:: ArgumentParser.parse_args(args=None, namespace=None) Convert argument strings to objects and assign them as attributes of the namespace. Return the populated namespace. @@ -1140,6 +1147,7 @@ The parse_args() method By default, the arg strings are taken from :data:`sys.argv`, and a new empty :class:`Namespace` object is created for the attributes. + Option value syntax ^^^^^^^^^^^^^^^^^^^ @@ -1503,7 +1511,7 @@ FileType objects Argument groups ^^^^^^^^^^^^^^^ -.. method:: ArgumentParser.add_argument_group([title], [description]) +.. method:: ArgumentParser.add_argument_group(title=None, description=None) By default, :class:`ArgumentParser` groups command-line arguments into "positional arguments" and "optional arguments" when displaying help @@ -1527,7 +1535,7 @@ Argument groups :class:`ArgumentParser`. When an argument is added to the group, the parser treats it just like a normal argument, but displays the argument in a separate group for help messages. The :meth:`add_argument_group` method - accepts ``title`` and ``description`` arguments which can be used to + accepts *title* and *description* arguments which can be used to customize this display:: >>> parser = argparse.ArgumentParser(prog='PROG', add_help=False) @@ -1555,7 +1563,7 @@ Argument groups Mutual exclusion ^^^^^^^^^^^^^^^^ -.. method:: add_mutually_exclusive_group([required=False]) +.. method:: add_mutually_exclusive_group(required=False) Create a mutually exclusive group. argparse will make sure that only one of the arguments in the mutually exclusive group was present on the command @@ -1573,7 +1581,7 @@ Mutual exclusion usage: PROG [-h] [--foo | --bar] PROG: error: argument --bar: not allowed with argument --foo - The :meth:`add_mutually_exclusive_group` method also accepts a ``required`` + The :meth:`add_mutually_exclusive_group` method also accepts a *required* argument, to indicate that at least one of the mutually exclusive arguments is required:: @@ -1586,7 +1594,7 @@ Mutual exclusion PROG: error: one of the arguments --foo --bar is required Note that currently mutually exclusive argument groups do not support the - ``title`` and ``description`` arguments of :meth:`add_argument_group`. + *title* and *description* arguments of :meth:`add_argument_group`. Parser defaults @@ -1637,37 +1645,36 @@ In most typical applications, :meth:`parse_args` will take care of formatting and printing any usage or error messages. However, several formatting methods are available: -.. method:: ArgumentParser.print_usage([file]): +.. method:: ArgumentParser.print_usage(file=None) Print a brief description of how the :class:`ArgumentParser` should be - invoked on the command line. If ``file`` is not present, ``sys.stderr`` is + invoked on the command line. If *file* is ``None``, :data:`sys.stderr` is assumed. -.. method:: ArgumentParser.print_help([file]): +.. method:: ArgumentParser.print_help(file=None) Print a help message, including the program usage and information about the - arguments registered with the :class:`ArgumentParser`. If ``file`` is not - present, ``sys.stderr`` is assumed. + arguments registered with the :class:`ArgumentParser`. If *file* is + ``None``, :data:`sys.stderr` is assumed. There are also variants of these methods that simply return a string instead of printing it: -.. method:: ArgumentParser.format_usage(): +.. method:: ArgumentParser.format_usage() Return a string containing a brief description of how the :class:`ArgumentParser` should be invoked on the command line. -.. method:: ArgumentParser.format_help(): +.. method:: ArgumentParser.format_help() Return a string containing a help message, including the program usage and information about the arguments registered with the :class:`ArgumentParser`. - Partial parsing ^^^^^^^^^^^^^^^ -.. method:: ArgumentParser.parse_known_args([args], [namespace]) +.. method:: ArgumentParser.parse_known_args(args=None, namespace=None) Sometimes a script may only parse a few of the command line arguments, passing the remaining arguments on to another script or program. In these cases, the @@ -1690,12 +1697,12 @@ Customizing file parsing .. method:: ArgumentParser.convert_arg_line_to_args(arg_line) - Arguments that are read from a file (see the ``fromfile_prefix_chars`` + Arguments that are read from a file (see the *fromfile_prefix_chars* keyword argument to the :class:`ArgumentParser` constructor) are read one argument per line. :meth:`convert_arg_line_to_args` can be overriden for fancier reading. - This method takes a single argument ``arg_line`` which is a string read from + This method takes a single argument *arg_line* which is a string read from the argument file. It returns a list of arguments parsed from this string. The method is called once per line read from the argument file, in order. @@ -1709,6 +1716,20 @@ Customizing file parsing yield arg +Exiting methods +^^^^^^^^^^^^^^^ + +.. method:: ArgumentParser.exit(status=0, message=None) + + This method terminates the program, exiting with the specified *status* + and, if given, it prints a *message* before that. + +.. method:: ArgumentParser.error(message) + + This method prints a usage message including the *message* to the + standard output and terminates the program with a status code of 2. + + .. _argparse-from-optparse: Upgrading optparse code diff --git a/Doc/library/base64.rst b/Doc/library/base64.rst index 084660d66e..ab85436cd6 100644 --- a/Doc/library/base64.rst +++ b/Doc/library/base64.rst @@ -1,4 +1,3 @@ - :mod:`base64` --- RFC 3548: Base16, Base32, Base64 Data Encodings ================================================================= diff --git a/Doc/library/dis.rst b/Doc/library/dis.rst index ac8d653c22..9addfe7402 100644 --- a/Doc/library/dis.rst +++ b/Doc/library/dis.rst @@ -99,7 +99,7 @@ The :mod:`dis` module defines the following functions and constants: .. data:: opmap - Dictionary mapping bytecodes to operation names. + Dictionary mapping operation names to bytecodes. .. data:: cmp_op diff --git a/Doc/library/hmac.rst b/Doc/library/hmac.rst index 8b3b92b716..480d0a7b48 100644 --- a/Doc/library/hmac.rst +++ b/Doc/library/hmac.rst @@ -19,10 +19,6 @@ This module implements the HMAC algorithm as described by :rfc:`2104`. is made. *digestmod* is the digest constructor or module for the HMAC object to use. It defaults to the :func:`hashlib.md5` constructor. - .. note:: - - The md5 hash has known weaknesses but remains the default for backwards - compatibility. Choose a better one for your application. An HMAC object has the following methods: diff --git a/Doc/library/os.rst b/Doc/library/os.rst index b920d4e102..194a0c4d76 100644 --- a/Doc/library/os.rst +++ b/Doc/library/os.rst @@ -1679,15 +1679,15 @@ to be ignored. .. function:: _exit(n) - Exit to the system with status *n*, without calling cleanup handlers, flushing + Exit the process with status *n*, without calling cleanup handlers, flushing stdio buffers, etc. Availability: Unix, Windows. .. note:: - The standard way to exit is ``sys.exit(n)``. :func:`_exit` should normally only - be used in the child process after a :func:`fork`. + The standard way to exit is ``sys.exit(n)``. :func:`_exit` should + normally only be used in the child process after a :func:`fork`. The following exit codes are defined and can be used with :func:`_exit`, although they are not required. These are typically used for system programs diff --git a/Doc/library/parser.rst b/Doc/library/parser.rst index 8fba6dfc87..9049c825cb 100644 --- a/Doc/library/parser.rst +++ b/Doc/library/parser.rst @@ -322,22 +322,8 @@ ST objects have the following methods: Same as ``st2tuple(st, line_info)``. -.. _st-examples: - -Examples --------- - -.. index:: builtin: compile - -The parser modules allows operations to be performed on the parse tree of Python -source code before the :term:`bytecode` is generated, and provides for inspection of the -parse tree for information gathering purposes. Two examples are presented. The -simple example demonstrates emulation of the :func:`compile` built-in function -and the complex example shows the use of a parse tree for information discovery. - - -Emulation of :func:`compile` -^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +Example: Emulation of :func:`compile` +------------------------------------- While many useful operations may take place between parsing and bytecode generation, the simplest operation is to do nothing. For this purpose, using @@ -371,322 +357,3 @@ readily available functions:: def load_expression(source_string): st = parser.expr(source_string) return st, st.compile() - - -Information Discovery -^^^^^^^^^^^^^^^^^^^^^ - -.. index:: - single: string; documentation - single: docstrings - -Some applications benefit from direct access to the parse tree. The remainder -of this section demonstrates how the parse tree provides access to module -documentation defined in docstrings without requiring that the code being -examined be loaded into a running interpreter via :keyword:`import`. This can -be very useful for performing analyses of untrusted code. - -Generally, the example will demonstrate how the parse tree may be traversed to -distill interesting information. Two functions and a set of classes are -developed which provide programmatic access to high level function and class -definitions provided by a module. The classes extract information from the -parse tree and provide access to the information at a useful semantic level, one -function provides a simple low-level pattern matching capability, and the other -function defines a high-level interface to the classes by handling file -operations on behalf of the caller. All source files mentioned here which are -not part of the Python installation are located in the :file:`Demo/parser/` -directory of the distribution. - -The dynamic nature of Python allows the programmer a great deal of flexibility, -but most modules need only a limited measure of this when defining classes, -functions, and methods. In this example, the only definitions that will be -considered are those which are defined in the top level of their context, e.g., -a function defined by a :keyword:`def` statement at column zero of a module, but -not a function defined within a branch of an :keyword:`if` ... :keyword:`else` -construct, though there are some good reasons for doing so in some situations. -Nesting of definitions will be handled by the code developed in the example. - -To construct the upper-level extraction methods, we need to know what the parse -tree structure looks like and how much of it we actually need to be concerned -about. Python uses a moderately deep parse tree so there are a large number of -intermediate nodes. It is important to read and understand the formal grammar -used by Python. This is specified in the file :file:`Grammar/Grammar` in the -distribution. Consider the simplest case of interest when searching for -docstrings: a module consisting of a docstring and nothing else. (See file -:file:`docstring.py`.) :: - - """Some documentation. - """ - -Using the interpreter to take a look at the parse tree, we find a bewildering -mass of numbers and parentheses, with the documentation buried deep in nested -tuples. :: - - >>> import parser - >>> import pprint - >>> st = parser.suite(open('docstring.py').read()) - >>> tup = st.totuple() - >>> pprint.pprint(tup) - (257, - (264, - (265, - (266, - (267, - (307, - (287, - (288, - (289, - (290, - (292, - (293, - (294, - (295, - (296, - (297, - (298, - (299, - (300, (3, '"""Some documentation.\n"""'))))))))))))))))), - (4, ''))), - (4, ''), - (0, '')) - -The numbers at the first element of each node in the tree are the node types; -they map directly to terminal and non-terminal symbols in the grammar. -Unfortunately, they are represented as integers in the internal representation, -and the Python structures generated do not change that. However, the -:mod:`symbol` and :mod:`token` modules provide symbolic names for the node types -and dictionaries which map from the integers to the symbolic names for the node -types. - -In the output presented above, the outermost tuple contains four elements: the -integer ``257`` and three additional tuples. Node type ``257`` has the symbolic -name :const:`file_input`. Each of these inner tuples contains an integer as the -first element; these integers, ``264``, ``4``, and ``0``, represent the node -types :const:`stmt`, :const:`NEWLINE`, and :const:`ENDMARKER`, respectively. -Note that these values may change depending on the version of Python you are -using; consult :file:`symbol.py` and :file:`token.py` for details of the -mapping. It should be fairly clear that the outermost node is related primarily -to the input source rather than the contents of the file, and may be disregarded -for the moment. The :const:`stmt` node is much more interesting. In -particular, all docstrings are found in subtrees which are formed exactly as -this node is formed, with the only difference being the string itself. The -association between the docstring in a similar tree and the defined entity -(class, function, or module) which it describes is given by the position of the -docstring subtree within the tree defining the described structure. - -By replacing the actual docstring with something to signify a variable component -of the tree, we allow a simple pattern matching approach to check any given -subtree for equivalence to the general pattern for docstrings. Since the -example demonstrates information extraction, we can safely require that the tree -be in tuple form rather than list form, allowing a simple variable -representation to be ``['variable_name']``. A simple recursive function can -implement the pattern matching, returning a Boolean and a dictionary of variable -name to value mappings. (See file :file:`example.py`.) :: - - from types import ListType, TupleType - - def match(pattern, data, vars=None): - if vars is None: - vars = {} - if type(pattern) is ListType: - vars[pattern[0]] = data - return 1, vars - if type(pattern) is not TupleType: - return (pattern == data), vars - if len(data) != len(pattern): - return 0, vars - for pattern, data in map(None, pattern, data): - same, vars = match(pattern, data, vars) - if not same: - break - return same, vars - -Using this simple representation for syntactic variables and the symbolic node -types, the pattern for the candidate docstring subtrees becomes fairly readable. -(See file :file:`example.py`.) :: - - import symbol - import token - - DOCSTRING_STMT_PATTERN = ( - symbol.stmt, - (symbol.simple_stmt, - (symbol.small_stmt, - (symbol.expr_stmt, - (symbol.testlist, - (symbol.test, - (symbol.and_test, - (symbol.not_test, - (symbol.comparison, - (symbol.expr, - (symbol.xor_expr, - (symbol.and_expr, - (symbol.shift_expr, - (symbol.arith_expr, - (symbol.term, - (symbol.factor, - (symbol.power, - (symbol.atom, - (token.STRING, ['docstring']) - )))))))))))))))), - (token.NEWLINE, '') - )) - -Using the :func:`match` function with this pattern, extracting the module -docstring from the parse tree created previously is easy:: - - >>> found, vars = match(DOCSTRING_STMT_PATTERN, tup[1]) - >>> found - 1 - >>> vars - {'docstring': '"""Some documentation.\n"""'} - -Once specific data can be extracted from a location where it is expected, the -question of where information can be expected needs to be answered. When -dealing with docstrings, the answer is fairly simple: the docstring is the first -:const:`stmt` node in a code block (:const:`file_input` or :const:`suite` node -types). A module consists of a single :const:`file_input` node, and class and -function definitions each contain exactly one :const:`suite` node. Classes and -functions are readily identified as subtrees of code block nodes which start -with ``(stmt, (compound_stmt, (classdef, ...`` or ``(stmt, (compound_stmt, -(funcdef, ...``. Note that these subtrees cannot be matched by :func:`match` -since it does not support multiple sibling nodes to match without regard to -number. A more elaborate matching function could be used to overcome this -limitation, but this is sufficient for the example. - -Given the ability to determine whether a statement might be a docstring and -extract the actual string from the statement, some work needs to be performed to -walk the parse tree for an entire module and extract information about the names -defined in each context of the module and associate any docstrings with the -names. The code to perform this work is not complicated, but bears some -explanation. - -The public interface to the classes is straightforward and should probably be -somewhat more flexible. Each "major" block of the module is described by an -object providing several methods for inquiry and a constructor which accepts at -least the subtree of the complete parse tree which it represents. The -:class:`ModuleInfo` constructor accepts an optional *name* parameter since it -cannot otherwise determine the name of the module. - -The public classes include :class:`ClassInfo`, :class:`FunctionInfo`, and -:class:`ModuleInfo`. All objects provide the methods :meth:`get_name`, -:meth:`get_docstring`, :meth:`get_class_names`, and :meth:`get_class_info`. The -:class:`ClassInfo` objects support :meth:`get_method_names` and -:meth:`get_method_info` while the other classes provide -:meth:`get_function_names` and :meth:`get_function_info`. - -Within each of the forms of code block that the public classes represent, most -of the required information is in the same form and is accessed in the same way, -with classes having the distinction that functions defined at the top level are -referred to as "methods." Since the difference in nomenclature reflects a real -semantic distinction from functions defined outside of a class, the -implementation needs to maintain the distinction. Hence, most of the -functionality of the public classes can be implemented in a common base class, -:class:`SuiteInfoBase`, with the accessors for function and method information -provided elsewhere. Note that there is only one class which represents function -and method information; this parallels the use of the :keyword:`def` statement -to define both types of elements. - -Most of the accessor functions are declared in :class:`SuiteInfoBase` and do not -need to be overridden by subclasses. More importantly, the extraction of most -information from a parse tree is handled through a method called by the -:class:`SuiteInfoBase` constructor. The example code for most of the classes is -clear when read alongside the formal grammar, but the method which recursively -creates new information objects requires further examination. Here is the -relevant part of the :class:`SuiteInfoBase` definition from :file:`example.py`:: - - class SuiteInfoBase: - _docstring = '' - _name = '' - - def __init__(self, tree = None): - self._class_info = {} - self._function_info = {} - if tree: - self._extract_info(tree) - - def _extract_info(self, tree): - # extract docstring - if len(tree) == 2: - found, vars = match(DOCSTRING_STMT_PATTERN[1], tree[1]) - else: - found, vars = match(DOCSTRING_STMT_PATTERN, tree[3]) - if found: - self._docstring = eval(vars['docstring']) - # discover inner definitions - for node in tree[1:]: - found, vars = match(COMPOUND_STMT_PATTERN, node) - if found: - cstmt = vars['compound'] - if cstmt[0] == symbol.funcdef: - name = cstmt[2][1] - self._function_info[name] = FunctionInfo(cstmt) - elif cstmt[0] == symbol.classdef: - name = cstmt[2][1] - self._class_info[name] = ClassInfo(cstmt) - -After initializing some internal state, the constructor calls the -:meth:`_extract_info` method. This method performs the bulk of the information -extraction which takes place in the entire example. The extraction has two -distinct phases: the location of the docstring for the parse tree passed in, and -the discovery of additional definitions within the code block represented by the -parse tree. - -The initial :keyword:`if` test determines whether the nested suite is of the -"short form" or the "long form." The short form is used when the code block is -on the same line as the definition of the code block, as in :: - - def square(x): "Square an argument."; return x ** 2 - -while the long form uses an indented block and allows nested definitions:: - - def make_power(exp): - "Make a function that raises an argument to the exponent `exp`." - def raiser(x, y=exp): - return x ** y - return raiser - -When the short form is used, the code block may contain a docstring as the -first, and possibly only, :const:`small_stmt` element. The extraction of such a -docstring is slightly different and requires only a portion of the complete -pattern used in the more common case. As implemented, the docstring will only -be found if there is only one :const:`small_stmt` node in the -:const:`simple_stmt` node. Since most functions and methods which use the short -form do not provide a docstring, this may be considered sufficient. The -extraction of the docstring proceeds using the :func:`match` function as -described above, and the value of the docstring is stored as an attribute of the -:class:`SuiteInfoBase` object. - -After docstring extraction, a simple definition discovery algorithm operates on -the :const:`stmt` nodes of the :const:`suite` node. The special case of the -short form is not tested; since there are no :const:`stmt` nodes in the short -form, the algorithm will silently skip the single :const:`simple_stmt` node and -correctly not discover any nested definitions. - -Each statement in the code block is categorized as a class definition, function -or method definition, or something else. For the definition statements, the -name of the element defined is extracted and a representation object appropriate -to the definition is created with the defining subtree passed as an argument to -the constructor. The representation objects are stored in instance variables -and may be retrieved by name using the appropriate accessor methods. - -The public classes provide any accessors required which are more specific than -those provided by the :class:`SuiteInfoBase` class, but the real extraction -algorithm remains common to all forms of code blocks. A high-level function can -be used to extract the complete set of information from a source file. (See -file :file:`example.py`.) :: - - def get_docs(fileName): - import os - import parser - - source = open(fileName).read() - basename = os.path.basename(os.path.splitext(fileName)[0]) - st = parser.suite(source) - return ModuleInfo(st.totuple(), basename) - -This provides an easy-to-use interface to the documentation of a module. If -information is required which is not extracted by the code of this example, the -code may be extended at clearly defined points to provide additional -capabilities. - diff --git a/Doc/library/pickle.rst b/Doc/library/pickle.rst index 5466a7e04d..963468dffb 100644 --- a/Doc/library/pickle.rst +++ b/Doc/library/pickle.rst @@ -25,6 +25,12 @@ confusion, the terms used here are "pickling" and "unpickling". This documentation describes both the :mod:`pickle` module and the :mod:`cPickle` module. +.. warning:: + + The :mod:`pickle` module is not intended to be secure against erroneous or + maliciously constructed data. Never unpickle data received from an untrusted + or unauthenticated source. + Relationship to other Python modules ------------------------------------ @@ -74,12 +80,6 @@ The :mod:`pickle` module differs from :mod:`marshal` several significant ways: The :mod:`pickle` serialization format is guaranteed to be backwards compatible across Python releases. -.. warning:: - - The :mod:`pickle` module is not intended to be secure against erroneous or - maliciously constructed data. Never unpickle data received from an untrusted - or unauthenticated source. - Note that serialization is a more primitive notion than persistence; although :mod:`pickle` reads and writes file objects, it does not handle the issue of naming persistent objects, nor the (even more complicated) issue of concurrent diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst index d99d18489b..decb12da14 100644 --- a/Doc/library/stdtypes.rst +++ b/Doc/library/stdtypes.rst @@ -1944,15 +1944,12 @@ pairs within braces, for example: ``{'jack': 4098, 'sjoerd': 4127}`` or ``{4098: values are added as items to the dictionary. If a key is specified both in the positional argument and as a keyword argument, the value associated with the keyword is retained in the dictionary. For example, these all return a - dictionary equal to ``{"one": 2, "two": 3}``: + dictionary equal to ``{"one": 1, "two": 2}``: - * ``dict(one=2, two=3)`` - - * ``dict({'one': 2, 'two': 3})`` - - * ``dict(zip(('one', 'two'), (2, 3)))`` - - * ``dict([['two', 3], ['one', 2]])`` + * ``dict(one=1, two=2)`` + * ``dict({'one': 1, 'two': 2})`` + * ``dict(zip(('one', 'two'), (1, 2)))`` + * ``dict([['two', 2], ['one', 1]])`` The first example only works for keys that are valid Python identifiers; the others work with any valid keys. diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst index 3997627c92..e812b855df 100644 --- a/Doc/library/sys.rst +++ b/Doc/library/sys.rst @@ -53,6 +53,13 @@ always available. ``modules.keys()`` only lists the imported modules.) +.. function:: call_tracing(func, args) + + Call ``func(*args)``, while tracing is enabled. The tracing state is saved, + and restored afterwards. This is intended to be called from a debugger from + a checkpoint, to recursively debug some other code. + + .. data:: copyright A string containing the copyright pertaining to the Python interpreter. @@ -219,19 +226,25 @@ always available. Exit from Python. This is implemented by raising the :exc:`SystemExit` exception, so cleanup actions specified by finally clauses of :keyword:`try` - statements are honored, and it is possible to intercept the exit attempt at an - outer level. The optional argument *arg* can be an integer giving the exit - status (defaulting to zero), or another type of object. If it is an integer, - zero is considered "successful termination" and any nonzero value is considered - "abnormal termination" by shells and the like. Most systems require it to be in - the range 0-127, and produce undefined results otherwise. Some systems have a - convention for assigning specific meanings to specific exit codes, but these are - generally underdeveloped; Unix programs generally use 2 for command line syntax - errors and 1 for all other kind of errors. If another type of object is passed, - ``None`` is equivalent to passing zero, and any other object is printed to - ``sys.stderr`` and results in an exit code of 1. In particular, - ``sys.exit("some error message")`` is a quick way to exit a program when an - error occurs. + statements are honored, and it is possible to intercept the exit attempt at + an outer level. + + The optional argument *arg* can be an integer giving the exit status + (defaulting to zero), or another type of object. If it is an integer, zero + is considered "successful termination" and any nonzero value is considered + "abnormal termination" by shells and the like. Most systems require it to be + in the range 0-127, and produce undefined results otherwise. Some systems + have a convention for assigning specific meanings to specific exit codes, but + these are generally underdeveloped; Unix programs generally use 2 for command + line syntax errors and 1 for all other kind of errors. If another type of + object is passed, ``None`` is equivalent to passing zero, and any other + object is printed to :data:`stderr` and results in an exit code of 1. In + particular, ``sys.exit("some error message")`` is a quick way to exit a + program when an error occurs. + + Since :func:`exit` ultimately "only" raises an exception, it will only exit + the process when called from the main thread, and the exception is not + intercepted. .. data:: exitfunc diff --git a/Doc/tutorial/classes.rst b/Doc/tutorial/classes.rst index 38dd7fd564..bdaa5d236a 100644 --- a/Doc/tutorial/classes.rst +++ b/Doc/tutorial/classes.rst @@ -4,25 +4,26 @@ Classes ******* -Python's class mechanism adds classes to the language with a minimum of new -syntax and semantics. It is a mixture of the class mechanisms found in C++ and -Modula-3. As is true for modules, classes in Python do not put an absolute -barrier between definition and user, but rather rely on the politeness of the -user not to "break into the definition." The most important features of classes -are retained with full power, however: the class inheritance mechanism allows +Compared with other programming languages, Python's class mechanism adds classes +with a minimum of new syntax and semantics. It is a mixture of the class +mechanisms found in C++ and Modula-3. Python classes provide all the standard +features of Object Oriented Programming: the class inheritance mechanism allows multiple base classes, a derived class can override any methods of its base class or classes, and a method can call the method of a base class with the same -name. Objects can contain an arbitrary amount of data. - -In C++ terminology, all class members (including the data members) are *public*, -and all member functions are *virtual*. As in Modula-3, there are no shorthands -for referencing the object's members from its methods: the method function is -declared with an explicit first argument representing the object, which is -provided implicitly by the call. As in Smalltalk, classes themselves are -objects. This provides semantics for importing and renaming. Unlike C++ and -Modula-3, built-in types can be used as base classes for extension by the user. -Also, like in C++, most built-in operators with special syntax (arithmetic -operators, subscripting etc.) can be redefined for class instances. +name. Objects can contain arbitrary amounts and kinds of data. As is true for +modules, classes partake of the dynamic nature of Python: they are created at +runtime, and can be modified further after creation. + +In C++ terminology, normally class members (including the data members) are +*public* (except see below :ref:`tut-private`), and all member functions are +*virtual*. As in Modula-3, there are no shorthands for referencing the object's +members from its methods: the method function is declared with an explicit first +argument representing the object, which is provided implicitly by the call. As +in Smalltalk, classes themselves are objects. This provides semantics for +importing and renaming. Unlike C++ and Modula-3, built-in types can be used as +base classes for extension by the user. Also, like in C++, most built-in +operators with special syntax (arithmetic operators, subscripting etc.) can be +redefined for class instances. (Lacking universally accepted terminology to talk about classes, I will make occasional use of Smalltalk and C++ terms. I would use Modula-3 terms, since |