diff options
Diffstat (limited to 'Doc')
| -rw-r--r-- | Doc/ACKS.txt | 1 | ||||
| -rw-r--r-- | Doc/tutorial/classes.rst | 25 | ||||
| -rw-r--r-- | Doc/tutorial/interpreter.rst | 59 | ||||
| -rw-r--r-- | Doc/tutorial/introduction.rst | 6 |
4 files changed, 43 insertions, 48 deletions
diff --git a/Doc/ACKS.txt b/Doc/ACKS.txt index f695403..0b107c8 100644 --- a/Doc/ACKS.txt +++ b/Doc/ACKS.txt @@ -65,6 +65,7 @@ docs@python.org), and we'll be glad to correct the problem. * Harald Hanche-Olsen * Manus Hand * Gerhard Häring +* Peter Harris * Travis B. Hartwell * Tim Hatch * Janko Hauser diff --git a/Doc/tutorial/classes.rst b/Doc/tutorial/classes.rst index 696860d..8c45d1a 100644 --- a/Doc/tutorial/classes.rst +++ b/Doc/tutorial/classes.rst @@ -473,8 +473,8 @@ scope.) Multiple Inheritance -------------------- -Python supports a limited form of multiple inheritance as well. A class -definition with multiple base classes looks like this:: +Python supports a form of multiple inheritance as well. A class definition with +multiple base classes looks like this:: class DerivedClassName(Base1, Base2, Base3): <statement-1> @@ -483,15 +483,18 @@ definition with multiple base classes looks like this:: . <statement-N> -Formerly, the only rule was depth-first, left-to-right. Thus, if an attribute -was not found in :class:`DerivedClassName`, it was searched in :class:`Base1`, -then (recursively) in the base classes of :class:`Base1`, and only if it was not -found there, it was searched in :class:`Base2`, and so on. - -In the meantime, the method resolution order changes dynamically to support -cooperative calls to :func:`super`. This approach is known in some other -multiple-inheritance languages as call-next-method and is more powerful than the -super call found in single-inheritance languages. +For most purposes, in the simplest cases, you can think of the search for +attributes inherited from a parent class as depth-first, left-to-right, not +searching twice in the same class where there is an overlap in the hierarchy. +Thus, if an attribute is not found in :class:`DerivedClassName`, it is searched +for in :class:`Base1`, then (recursively) in the base classes of :class:`Base1`, +and if it was not found there, it was searched for in :class:`Base2`, and so on. + +In fact, it is slightly more complex than that; the method resolution order +changes dynamically to support cooperative calls to :func:`super`. This +approach is known in some other multiple-inheritance languages as +call-next-method and is more powerful than the super call found in +single-inheritance languages. Dynamic ordering is necessary because all cases of multiple inheritance exhibit one or more diamond relationships (where one at least one of the parent classes diff --git a/Doc/tutorial/interpreter.rst b/Doc/tutorial/interpreter.rst index ce78399..5c67ba9 100644 --- a/Doc/tutorial/interpreter.rst +++ b/Doc/tutorial/interpreter.rst @@ -101,11 +101,14 @@ with the *secondary prompt*, by default three dots (``...``). The interpreter prints a welcome message stating its version number and a copyright notice before printing the first prompt:: - python - Python 1.5.2b2 (#1, Feb 28 1999, 00:02:06) [GCC 2.8.1] on sunos5 - Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam + $ python + Python 3.0a1 (py3k, Sep 12 2007, 12:21:02) + [GCC 3.4.6 20060404 (Red Hat 3.4.6-8)] on linux2 + Type "help", "copyright", "credits" or "license" for more information. >>> +.. XXX update for final release of Python 3.0 + Continuation lines are needed when entering a multi-line construct. As an example, take a look at this :keyword:`if` statement:: @@ -170,44 +173,32 @@ The script can be given an executable mode, or permission, using the Source Code Encoding -------------------- -.. XXX out of date! +By default, Python source files are treated as encoded in UTF-8. In that +encoding, characters of most languages in the world can be used simultaneously +in string literals, identifiers and comments --- although the standard library +only uses ASCII characters for identifiers, a convention that any portable code +should follow. To display all these characters properly, your editor must +recognize that the file is UTF-8, and it must use a font that supports all the +characters in the file. -It is possible to use encodings different than ASCII in Python source files. The -best way to do it is to put one more special comment line right after the ``#!`` -line to define the source file encoding:: +It is also possible to specify a different encoding for source files. In order +to do this, put one more special comment line right after the ``#!`` line to +define the source file encoding:: # -*- coding: encoding -*- +With that declaration, everything in the source file will be treated as having +the encoding *encoding* instead of UTF-8. The list of possible encodings can be +found in the Python Library Reference, in the section on :mod:`codecs`. -With that declaration, all characters in the source file will be treated as -having the encoding *encoding*, and it will be possible to directly write -Unicode string literals in the selected encoding. The list of possible -encodings can be found in the Python Library Reference, in the section on -:mod:`codecs`. - -For example, to write Unicode literals including the Euro currency symbol, the -ISO-8859-15 encoding can be used, with the Euro symbol having the ordinal value -164. This script will print the value 8364 (the Unicode codepoint corresponding -to the Euro symbol) and then exit:: - - # -*- coding: iso-8859-15 -*- - - currency = u"€" - print(ord(currency)) +For example, if your editor of choice does not support UTF-8 encoded files and +insists on using some other encoding, say Windows-1252, you can write:: -If your editor supports saving files as ``UTF-8`` with a UTF-8 *byte order mark* -(aka BOM), you can use that instead of an encoding declaration. IDLE supports -this capability if ``Options/General/Default Source Encoding/UTF-8`` is set. -Notice that this signature is not understood in older Python releases (2.2 and -earlier), and also not understood by the operating system for script files with -``#!`` lines (only used on Unix systems). + # -*- coding: cp-1252 -*- -By using UTF-8 (either through the signature or an encoding declaration), -characters of most languages in the world can be used simultaneously in string -literals and comments. Using non-ASCII characters in identifiers is not -supported. To display all these characters properly, your editor must recognize -that the file is UTF-8, and it must use a font that supports all the characters -in the file. +and still use all characters in the Windows-1252 character set in the source +files. The special encoding comment must be in the *first or second* line +within the file. .. _tut-startup: diff --git a/Doc/tutorial/introduction.rst b/Doc/tutorial/introduction.rst index 1b24588..30adac9 100644 --- a/Doc/tutorial/introduction.rst +++ b/Doc/tutorial/introduction.rst @@ -131,9 +131,9 @@ and imaginary part. To extract these parts from a complex number *z*, use 0.5 The conversion functions to floating point and integer (:func:`float`, -:func:`int` and :func:`long`) don't work for complex numbers --- there is no one -correct way to convert a complex number to a real number. Use ``abs(z)`` to get -its magnitude (as a float) or ``z.real`` to get its real part. :: +:func:`int`) don't work for complex numbers --- there is not one correct way to +convert a complex number to a real number. Use ``abs(z)`` to get its magnitude +(as a float) or ``z.real`` to get its real part:: >>> a=3.0+4.0j >>> float(a) |