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,
:term:`abstract base class`.
floor division
- Mathematical division discarding any remainder. 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.
+ 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
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.
By importing the :mod:`__future__` module and evaluating its variables,
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
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
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