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Diffstat (limited to 'Doc')
| -rw-r--r-- | Doc/glossary.rst | 15 | ||||
| -rw-r--r-- | Doc/library/abc.rst | 8 |
2 files changed, 16 insertions, 7 deletions
diff --git a/Doc/glossary.rst b/Doc/glossary.rst index 0da14d8..693e4a7 100644 --- a/Doc/glossary.rst +++ b/Doc/glossary.rst @@ -24,6 +24,14 @@ Glossary 2to3 is available in the standard library as :mod:`lib2to3`; a standalone entry point is provided as :file:`Tools/scripts/2to3`. + Abstract Base Class + Abstract Base Classes (abbreviated ABCs) complement :term:`duck-typing` by + providing a way to define interfaces when other techniques like :func:`hasattr` + would be clumsy. Python comes with many builtin ABCs for data structures + (in the :mod:`collections` module), numbers (in the :mod:`numbers` + module), and streams (in the :mod:`io` module). You can create your own + ABC with the :mod:`abc` module. + argument A value passed to a function or method, assigned to a name local to the body. A function or method may have both positional arguments and @@ -116,15 +124,16 @@ Glossary be any object with a :meth:`__hash__` function, not just integers starting from zero. Called a hash in Perl. - duck-typing + duck-typing Pythonic programming style that determines an object's type by inspection of its method or attribute signature rather than by explicit relationship to some type object ("If it looks like a duck and quacks like a duck, it must be a duck.") By emphasizing interfaces rather than specific types, well-designed code improves its flexibility by allowing polymorphic substitution. Duck-typing avoids tests using :func:`type` or - :func:`isinstance`. Instead, it typically employs :func:`hasattr` tests or - :term:`EAFP` programming. + :func:`isinstance`. (Note, however, that duck-typing can be complemented + with abstract base classes.) Instead, it typically employs :func:`hasattr` + tests or :term:`EAFP` programming. EAFP Easier to ask for forgiveness than permission. This common Python coding diff --git a/Doc/library/abc.rst b/Doc/library/abc.rst index 5eee7cc..9cdb5b3 100644 --- a/Doc/library/abc.rst +++ b/Doc/library/abc.rst @@ -9,10 +9,10 @@ .. versionadded:: 2.6 -This module provides the infrastructure for defining abstract base classes -(ABCs) in Python, as outlined in :pep:`3119`; see the PEP for why this was added -to Python. (See also :pep:`3141` and the :mod:`numbers` module regarding a type -hierarchy for numbers based on ABCs.) +This module provides the infrastructure for defining :term:`abstract base +classes` (ABCs) in Python, as outlined in :pep:`3119`; see the PEP for why this +was added to Python. (See also :pep:`3141` and the :mod:`numbers` module +regarding a type hierarchy for numbers based on ABCs.) The :mod:`collections` module has some concrete classes that derive from ABCs; these can, of course, be further derived. In addition the |