[Python-checkins] r84426 - python/branches/release27-maint/Doc/glossary.rst

Thu Sep 2 00:25:41 CEST 2010

Author: raymond.hettinger
Date: Thu Sep 2 00:25:41 2010
New Revision: 84426
Log:
Glossary cleanup
Modified:
 python/branches/release27-maint/Doc/glossary.rst
Modified: python/branches/release27-maint/Doc/glossary.rst
==============================================================================

--- python/branches/release27-maint/Doc/glossary.rst	(original)
+++ python/branches/release27-maint/Doc/glossary.rst	Thu Sep 2 00:25:41 2010
@@ -143,10 +143,9 @@
 For more information about descriptors' methods, see :ref:`descriptors`.
 
 dictionary
- An associative array, where arbitrary keys are mapped to values. The use
- of :class:`dict` closely resembles that for :class:`list`, but the keys can
- be any object with a :meth:`__hash__` function, not just integers.
- Called a hash in Perl.
+ An associative array, where arbitrary keys are mapped to values. The keys
+ can be any object with :meth:`__hash__` function and :meth:`__eq__`
+ methods. Called a hash in Perl.
 
 docstring
 A string literal which appears as the first expression in a class,
@@ -193,13 +192,20 @@
 implement a method named :meth:`find_module`. See :pep:`302` for
 details.
 
+ floor division
+ Mathematical division that rounds down to nearest integer. The floor
+ division operator is ``//``. For example, the expression ``11 // 4``
+ evaluates to ``2`` in contrast to the ``2.75`` returned by float true
+ division. Note that ``(-11) // 4`` is ``-3`` because that is ``-2.75``
+ rounded *downward*. See :pep:`238`.
+
 function
 A series of statements which returns some value to a caller. It can also
 be passed zero or more arguments which may be used in the execution of
 the body. See also :term:`argument` and :term:`method`.
 
 __future__
- A pseudo module which programmers can use to enable new language features
+ A pseudo-module which programmers can use to enable new language features
 which are not compatible with the current interpreter. For example, the
 expression ``11/4`` currently evaluates to ``2``. If the module in which
 it is executed had enabled *true division* by executing::
@@ -224,13 +230,13 @@
 
 generator
 A function which returns an iterator. It looks like a normal function
- except that values are returned to the caller using a :keyword:`yield`
- statement instead of a :keyword:`return` statement. Generator functions
- often contain one or more :keyword:`for` or :keyword:`while` loops which
- :keyword:`yield` elements back to the caller. The function execution is
- stopped at the :keyword:`yield` keyword (returning the result) and is
- resumed there when the next element is requested by calling the
- :meth:`next` method of the returned iterator.
+ except that it contains :keyword:`yield` statements for producing a series
+ a values usable in a for-loop or that can be retrieved one at a time with
+ the :func:`next` function. Each :keyword:`yield` temporarily suspends
+ processing, remembering the location execution state (including local
+ variables and pending try-statements). When the generator resumes, it
+ picks-up where it left-off (in contrast to functions which start fresh on
+ every invocation).
 
 .. index:: single: generator expression
 
@@ -275,9 +281,7 @@
 IDLE
 An Integrated Development Environment for Python. IDLE is a basic editor
 and interpreter environment which ships with the standard distribution of
- Python. Good for beginners, it also serves as clear example code for
- those wanting to implement a moderately sophisticated, multi-platform GUI
- application.
+ Python.
 
 immutable
 An object with a fixed value. Immutable objects include numbers, strings and
@@ -389,7 +393,8 @@
 
 mapping
 A container object (such as :class:`dict`) which supports arbitrary key
- lookups using the special method :meth:`__getitem__`.
+ lookups using the special method :meth:`__getitem__`. Mappings also
+ support :meth:`__len__`, :meth:`__iter__`, and :meth:`__contains__`.
 
 metaclass
 The class of a class. Class definitions create a class name, a class
