symbian-qemu-0.9.1-12/python-2.6.1/Doc/library/pprint.rst
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+
+:mod:`pprint` --- Data pretty printer
+=====================================
+
+.. module:: pprint
+   :synopsis: Data pretty printer.
+.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+The :mod:`pprint` module provides a capability to "pretty-print" arbitrary
+Python data structures in a form which can be used as input to the interpreter.
+If the formatted structures include objects which are not fundamental Python
+types, the representation may not be loadable.  This may be the case if objects
+such as files, sockets, classes, or instances are included, as well as many
+other builtin objects which are not representable as Python constants.
+
+The formatted representation keeps objects on a single line if it can, and
+breaks them onto multiple lines if they don't fit within the allowed width.
+Construct :class:`PrettyPrinter` objects explicitly if you need to adjust the
+width constraint.
+
+.. versionchanged:: 2.5
+   Dictionaries are sorted by key before the display is computed; before 2.5, a
+   dictionary was sorted only if its display required more than one line, although
+   that wasn't documented.
+
+.. versionchanged:: 2.6
+   Added support for :class:`set` and :class:`frozenset`.
+
+The :mod:`pprint` module defines one class:
+
+.. First the implementation class:
+
+
+.. class:: PrettyPrinter(...)
+
+   Construct a :class:`PrettyPrinter` instance.  This constructor understands
+   several keyword parameters.  An output stream may be set using the *stream*
+   keyword; the only method used on the stream object is the file protocol's
+   :meth:`write` method.  If not specified, the :class:`PrettyPrinter` adopts
+   ``sys.stdout``.  Three additional parameters may be used to control the
+   formatted representation.  The keywords are *indent*, *depth*, and *width*.  The
+   amount of indentation added for each recursive level is specified by *indent*;
+   the default is one.  Other values can cause output to look a little odd, but can
+   make nesting easier to spot.  The number of levels which may be printed is
+   controlled by *depth*; if the data structure being printed is too deep, the next
+   contained level is replaced by ``...``.  By default, there is no constraint on
+   the depth of the objects being formatted.  The desired output width is
+   constrained using the *width* parameter; the default is 80 characters.  If a
+   structure cannot be formatted within the constrained width, a best effort will
+   be made.
+
+      >>> import pprint
+      >>> stuff = ['spam', 'eggs', 'lumberjack', 'knights', 'ni']
+      >>> stuff.insert(0, stuff[:])
+      >>> pp = pprint.PrettyPrinter(indent=4)
+      >>> pp.pprint(stuff)
+      [   ['spam', 'eggs', 'lumberjack', 'knights', 'ni'],
+          'spam',
+          'eggs',
+          'lumberjack',
+          'knights',
+          'ni']
+      >>> tup = ('spam', ('eggs', ('lumberjack', ('knights', ('ni', ('dead',
+      ... ('parrot', ('fresh fruit',))))))))
+      >>> pp = pprint.PrettyPrinter(depth=6)
+      >>> pp.pprint(tup)
+      ('spam', ('eggs', ('lumberjack', ('knights', ('ni', ('dead', (...)))))))
+
+The :class:`PrettyPrinter` class supports several derivative functions:
+
+.. Now the derivative functions:
+
+.. function:: pformat(object[, indent[, width[, depth]]])
+
+   Return the formatted representation of *object* as a string.  *indent*, *width*
+   and *depth* will be passed to the :class:`PrettyPrinter` constructor as
+   formatting parameters.
+
+   .. versionchanged:: 2.4
+      The parameters *indent*, *width* and *depth* were added.
+
+
+.. function:: pprint(object[, stream[, indent[, width[, depth]]]])
+
+   Prints the formatted representation of *object* on *stream*, followed by a
+   newline.  If *stream* is omitted, ``sys.stdout`` is used.  This may be used in
+   the interactive interpreter instead of a :keyword:`print` statement for
+   inspecting values.    *indent*, *width* and *depth* will be passed to the
+   :class:`PrettyPrinter` constructor as formatting parameters.
+
+      >>> import pprint
+      >>> stuff = ['spam', 'eggs', 'lumberjack', 'knights', 'ni']
+      >>> stuff.insert(0, stuff)
+      >>> pprint.pprint(stuff)
+      [<Recursion on list with id=...>,
+       'spam',
+       'eggs',
+       'lumberjack',
+       'knights',
+       'ni']
+
+   .. versionchanged:: 2.4
+      The parameters *indent*, *width* and *depth* were added.
+
+
+.. function:: isreadable(object)
+
+   .. index:: builtin: eval
+
+   Determine if the formatted representation of *object* is "readable," or can be
+   used to reconstruct the value using :func:`eval`.  This always returns ``False``
+   for recursive objects.
+
+      >>> pprint.isreadable(stuff)
+      False
+
+
+.. function:: isrecursive(object)
+
+   Determine if *object* requires a recursive representation.
+
+
+One more support function is also defined:
+
+.. function:: saferepr(object)
+
+   Return a string representation of *object*, protected against recursive data
+   structures.  If the representation of *object* exposes a recursive entry, the
+   recursive reference will be represented as ``<Recursion on typename with
+   id=number>``.  The representation is not otherwise formatted.
+
+   >>> pprint.saferepr(stuff)
+   "[<Recursion on list with id=...>, 'spam', 'eggs', 'lumberjack', 'knights', 'ni']"
+
+
+.. _prettyprinter-objects:
+
+PrettyPrinter Objects
+---------------------
+
+:class:`PrettyPrinter` instances have the following methods:
+
+
+.. method:: PrettyPrinter.pformat(object)
+
+   Return the formatted representation of *object*.  This takes into account the
+   options passed to the :class:`PrettyPrinter` constructor.
+
+
+.. method:: PrettyPrinter.pprint(object)
+
+   Print the formatted representation of *object* on the configured stream,
+   followed by a newline.
+
+The following methods provide the implementations for the corresponding
+functions of the same names.  Using these methods on an instance is slightly
+more efficient since new :class:`PrettyPrinter` objects don't need to be
+created.
+
+
+.. method:: PrettyPrinter.isreadable(object)
+
+   .. index:: builtin: eval
+
+   Determine if the formatted representation of the object is "readable," or can be
+   used to reconstruct the value using :func:`eval`.  Note that this returns
+   ``False`` for recursive objects.  If the *depth* parameter of the
+   :class:`PrettyPrinter` is set and the object is deeper than allowed, this
+   returns ``False``.
+
+
+.. method:: PrettyPrinter.isrecursive(object)
+
+   Determine if the object requires a recursive representation.
+
+This method is provided as a hook to allow subclasses to modify the way objects
+are converted to strings.  The default implementation uses the internals of the
+:func:`saferepr` implementation.
+
+
+.. method:: PrettyPrinter.format(object, context, maxlevels, level)
+
+   Returns three values: the formatted version of *object* as a string, a flag
+   indicating whether the result is readable, and a flag indicating whether
+   recursion was detected.  The first argument is the object to be presented.  The
+   second is a dictionary which contains the :func:`id` of objects that are part of
+   the current presentation context (direct and indirect containers for *object*
+   that are affecting the presentation) as the keys; if an object needs to be
+   presented which is already represented in *context*, the third return value
+   should be ``True``.  Recursive calls to the :meth:`format` method should add
+   additional entries for containers to this dictionary.  The third argument,
+   *maxlevels*, gives the requested limit to recursion; this will be ``0`` if there
+   is no requested limit.  This argument should be passed unmodified to recursive
+   calls. The fourth argument, *level*, gives the current level; recursive calls
+   should be passed a value less than that of the current call.
+
+   .. versionadded:: 2.3
+
+.. _pprint-example:
+
+pprint Example
+--------------
+
+This example demonstrates several uses of the :func:`pprint` function and its parameters.
+
+   >>> import pprint
+   >>> tup = ('spam', ('eggs', ('lumberjack', ('knights', ('ni', ('dead',
+   ... ('parrot', ('fresh fruit',))))))))
+   >>> stuff = ['a' * 10, tup, ['a' * 30, 'b' * 30], ['c' * 20, 'd' * 20]]
+   >>> pprint.pprint(stuff)
+   ['aaaaaaaaaa',
+    ('spam',
+     ('eggs',
+      ('lumberjack',
+       ('knights', ('ni', ('dead', ('parrot', ('fresh fruit',)))))))),
+    ['aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa', 'bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'],
+    ['cccccccccccccccccccc', 'dddddddddddddddddddd']]
+   >>> pprint.pprint(stuff, depth=3)
+   ['aaaaaaaaaa',
+    ('spam', ('eggs', (...))),
+    ['aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa', 'bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'],
+    ['cccccccccccccccccccc', 'dddddddddddddddddddd']]
+   >>> pprint.pprint(stuff, width=60)
+   ['aaaaaaaaaa',
+    ('spam',
+     ('eggs',
+      ('lumberjack',
+       ('knights',
+        ('ni', ('dead', ('parrot', ('fresh fruit',)))))))),
+    ['aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa',
+     'bbbbbbbbbbbbbbbbbbbbbbbbbbbbbb'],
+    ['cccccccccccccccccccc', 'dddddddddddddddddddd']]
+