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# SOME DESCRIPTIVE TITLE.
# Copyright (C) 2001-2017, Python Software Foundation
# This file is distributed under the same license as the Python package.
# FIRST AUTHOR <EMAIL@ADDRESS>, 2017.
#
#, fuzzy
msgid ""
msgstr ""
"Project-Id-Version: Python 3.6\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2019-07-15 15:23+0900\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=utf-8\n"
"Content-Transfer-Encoding: 8bit\n"
"Generated-By: Babel 2.7.0\n"
#: ../Doc/faq/programming.rst:5
msgid "Programming FAQ"
msgstr ""
#: ../Doc/faq/programming.rst:8
msgid "Contents"
msgstr ""
#: ../Doc/faq/programming.rst:12
msgid "General Questions"
msgstr ""
#: ../Doc/faq/programming.rst:15
msgid ""
"Is there a source code level debugger with breakpoints, single-stepping, "
"etc.?"
msgstr ""
#: ../Doc/faq/programming.rst:17 ../Doc/faq/programming.rst:63
msgid "Yes."
msgstr ""
#: ../Doc/faq/programming.rst:19
msgid ""
"Several debuggers for Python are described below, and the built-in "
"function :func:`breakpoint` allows you to drop into any of them."
msgstr ""
#: ../Doc/faq/programming.rst:22
msgid ""
"The pdb module is a simple but adequate console-mode debugger for Python."
" It is part of the standard Python library, and is :mod:`documented in "
"the Library Reference Manual <pdb>`. You can also write your own debugger"
" by using the code for pdb as an example."
msgstr ""
#: ../Doc/faq/programming.rst:27
msgid ""
"The IDLE interactive development environment, which is part of the "
"standard Python distribution (normally available as Tools/scripts/idle), "
"includes a graphical debugger."
msgstr ""
#: ../Doc/faq/programming.rst:31
msgid ""
"PythonWin is a Python IDE that includes a GUI debugger based on pdb. The"
" Pythonwin debugger colors breakpoints and has quite a few cool features "
"such as debugging non-Pythonwin programs. Pythonwin is available as part"
" of the `Python for Windows Extensions "
"<https://sourceforge.net/projects/pywin32/>`__ project and as a part of "
"the ActivePython distribution (see "
"https://www.activestate.com/activepython\\ )."
msgstr ""
#: ../Doc/faq/programming.rst:38
msgid ""
"`Boa Constructor <http://boa-constructor.sourceforge.net/>`_ is an IDE "
"and GUI builder that uses wxWidgets. It offers visual frame creation and"
" manipulation, an object inspector, many views on the source like object "
"browsers, inheritance hierarchies, doc string generated html "
"documentation, an advanced debugger, integrated help, and Zope support."
msgstr ""
#: ../Doc/faq/programming.rst:44
msgid ""
"`Eric <http://eric-ide.python-projects.org/>`_ is an IDE built on PyQt "
"and the Scintilla editing component."
msgstr ""
#: ../Doc/faq/programming.rst:47
msgid ""
"Pydb is a version of the standard Python debugger pdb, modified for use "
"with DDD (Data Display Debugger), a popular graphical debugger front end."
" Pydb can be found at http://bashdb.sourceforge.net/pydb/ and DDD can be"
" found at https://www.gnu.org/software/ddd."
msgstr ""
#: ../Doc/faq/programming.rst:52
msgid ""
"There are a number of commercial Python IDEs that include graphical "
"debuggers. They include:"
msgstr ""
#: ../Doc/faq/programming.rst:55
msgid "Wing IDE (https://wingware.com/)"
msgstr ""
#: ../Doc/faq/programming.rst:56
msgid "Komodo IDE (https://komodoide.com/)"
msgstr ""
#: ../Doc/faq/programming.rst:57
msgid "PyCharm (https://www.jetbrains.com/pycharm/)"
msgstr ""
#: ../Doc/faq/programming.rst:61
msgid "Is there a tool to help find bugs or perform static analysis?"
msgstr ""
#: ../Doc/faq/programming.rst:65
msgid ""
"PyChecker is a static analysis tool that finds bugs in Python source code"
" and warns about code complexity and style. You can get PyChecker from "
"http://pychecker.sourceforge.net/."
msgstr ""
#: ../Doc/faq/programming.rst:69
msgid ""
"`Pylint <https://www.pylint.org/>`_ is another tool that checks if a "
"module satisfies a coding standard, and also makes it possible to write "
"plug-ins to add a custom feature. In addition to the bug checking that "
"PyChecker performs, Pylint offers some additional features such as "
"checking line length, whether variable names are well-formed according to"
" your coding standard, whether declared interfaces are fully implemented,"
" and more. https://docs.pylint.org/ provides a full list of Pylint's "
"features."
msgstr ""
#: ../Doc/faq/programming.rst:77
msgid ""
"Static type checkers such as `Mypy <http://mypy-lang.org/>`_, `Pyre "
"<https://pyre-check.org/>`_, and `Pytype "
"<https://github.com/google/pytype>`_ can check type hints in Python "
"source code."
msgstr ""
#: ../Doc/faq/programming.rst:84
msgid "How can I create a stand-alone binary from a Python script?"
msgstr ""
#: ../Doc/faq/programming.rst:86
msgid ""
"You don't need the ability to compile Python to C code if all you want is"
" a stand-alone program that users can download and run without having to "
"install the Python distribution first. There are a number of tools that "
"determine the set of modules required by a program and bind these modules"
" together with a Python binary to produce a single executable."
msgstr ""
#: ../Doc/faq/programming.rst:92
msgid ""
"One is to use the freeze tool, which is included in the Python source "
"tree as ``Tools/freeze``. It converts Python byte code to C arrays; a C "
"compiler you can embed all your modules into a new program, which is then"
" linked with the standard Python modules."
msgstr ""
#: ../Doc/faq/programming.rst:97
msgid ""
"It works by scanning your source recursively for import statements (in "
"both forms) and looking for the modules in the standard Python path as "
"well as in the source directory (for built-in modules). It then turns "
"the bytecode for modules written in Python into C code (array "
"initializers that can be turned into code objects using the marshal "
"module) and creates a custom-made config file that only contains those "
"built-in modules which are actually used in the program. It then "
"compiles the generated C code and links it with the rest of the Python "
"interpreter to form a self-contained binary which acts exactly like your "
"script."
msgstr ""
#: ../Doc/faq/programming.rst:106
msgid ""
"Obviously, freeze requires a C compiler. There are several other "
"utilities which don't. One is Thomas Heller's py2exe (Windows only) at"
msgstr ""
#: ../Doc/faq/programming.rst:109
msgid "http://www.py2exe.org/"
msgstr ""
#: ../Doc/faq/programming.rst:111
msgid ""
"Another tool is Anthony Tuininga's `cx_Freeze <https://anthony-"
"tuininga.github.io/cx_Freeze/>`_."
msgstr ""
#: ../Doc/faq/programming.rst:115
msgid "Are there coding standards or a style guide for Python programs?"
msgstr ""
#: ../Doc/faq/programming.rst:117
msgid ""
"Yes. The coding style required for standard library modules is "
"documented as :pep:`8`."
msgstr ""
#: ../Doc/faq/programming.rst:122
msgid "Core Language"
msgstr ""
#: ../Doc/faq/programming.rst:125
msgid "Why am I getting an UnboundLocalError when the variable has a value?"
msgstr ""
#: ../Doc/faq/programming.rst:127
msgid ""
"It can be a surprise to get the UnboundLocalError in previously working "
"code when it is modified by adding an assignment statement somewhere in "
"the body of a function."
msgstr ""
#: ../Doc/faq/programming.rst:131
msgid "This code:"
msgstr ""
#: ../Doc/faq/programming.rst:139
msgid "works, but this code:"
msgstr ""
#: ../Doc/faq/programming.rst:146
msgid "results in an UnboundLocalError:"
msgstr ""
#: ../Doc/faq/programming.rst:153
msgid ""
"This is because when you make an assignment to a variable in a scope, "
"that variable becomes local to that scope and shadows any similarly named"
" variable in the outer scope. Since the last statement in foo assigns a "
"new value to ``x``, the compiler recognizes it as a local variable. "
"Consequently when the earlier ``print(x)`` attempts to print the "
"uninitialized local variable and an error results."
msgstr ""
#: ../Doc/faq/programming.rst:160
msgid ""
"In the example above you can access the outer scope variable by declaring"
" it global:"
msgstr ""
#: ../Doc/faq/programming.rst:171
msgid ""
"This explicit declaration is required in order to remind you that (unlike"
" the superficially analogous situation with class and instance variables)"
" you are actually modifying the value of the variable in the outer scope:"
msgstr ""
#: ../Doc/faq/programming.rst:178
msgid ""
"You can do a similar thing in a nested scope using the "
":keyword:`nonlocal` keyword:"
msgstr ""
#: ../Doc/faq/programming.rst:195
msgid "What are the rules for local and global variables in Python?"
msgstr ""
#: ../Doc/faq/programming.rst:197
msgid ""
"In Python, variables that are only referenced inside a function are "
"implicitly global. If a variable is assigned a value anywhere within the"
" function's body, it's assumed to be a local unless explicitly declared "
"as global."
msgstr ""
#: ../Doc/faq/programming.rst:201
msgid ""
"Though a bit surprising at first, a moment's consideration explains this."
" On one hand, requiring :keyword:`global` for assigned variables "
"provides a bar against unintended side-effects. On the other hand, if "
"``global`` was required for all global references, you'd be using "
"``global`` all the time. You'd have to declare as global every reference"
" to a built-in function or to a component of an imported module. This "
"clutter would defeat the usefulness of the ``global`` declaration for "
"identifying side-effects."
msgstr ""
#: ../Doc/faq/programming.rst:211
msgid ""
"Why do lambdas defined in a loop with different values all return the "
"same result?"
msgstr ""
#: ../Doc/faq/programming.rst:213
msgid ""
"Assume you use a for loop to define a few different lambdas (or even "
"plain functions), e.g.::"
msgstr ""
#: ../Doc/faq/programming.rst:220
msgid ""
"This gives you a list that contains 5 lambdas that calculate ``x**2``. "
"You might expect that, when called, they would return, respectively, "
"``0``, ``1``, ``4``, ``9``, and ``16``. However, when you actually try "
"you will see that they all return ``16``::"
msgstr ""
#: ../Doc/faq/programming.rst:230
msgid ""
"This happens because ``x`` is not local to the lambdas, but is defined in"
" the outer scope, and it is accessed when the lambda is called --- not "
"when it is defined. At the end of the loop, the value of ``x`` is ``4``,"
" so all the functions now return ``4**2``, i.e. ``16``. You can also "
"verify this by changing the value of ``x`` and see how the results of the"
" lambdas change::"
msgstr ""
#: ../Doc/faq/programming.rst:240
msgid ""
"In order to avoid this, you need to save the values in variables local to"
" the lambdas, so that they don't rely on the value of the global ``x``::"
msgstr ""
#: ../Doc/faq/programming.rst:247
msgid ""
"Here, ``n=x`` creates a new variable ``n`` local to the lambda and "
"computed when the lambda is defined so that it has the same value that "
"``x`` had at that point in the loop. This means that the value of ``n`` "
"will be ``0`` in the first lambda, ``1`` in the second, ``2`` in the "
"third, and so on. Therefore each lambda will now return the correct "
"result::"
msgstr ""
#: ../Doc/faq/programming.rst:258
msgid ""
"Note that this behaviour is not peculiar to lambdas, but applies to "
"regular functions too."
msgstr ""
#: ../Doc/faq/programming.rst:263
msgid "How do I share global variables across modules?"
msgstr ""
#: ../Doc/faq/programming.rst:265
msgid ""
"The canonical way to share information across modules within a single "
"program is to create a special module (often called config or cfg). Just"
" import the config module in all modules of your application; the module "
"then becomes available as a global name. Because there is only one "
"instance of each module, any changes made to the module object get "
"reflected everywhere. For example:"
msgstr ""
#: ../Doc/faq/programming.rst:271
msgid "config.py::"
msgstr ""
#: ../Doc/faq/programming.rst:275
msgid "mod.py::"
msgstr ""
#: ../Doc/faq/programming.rst:280
msgid "main.py::"
msgstr ""
#: ../Doc/faq/programming.rst:286
msgid ""
"Note that using a module is also the basis for implementing the Singleton"
" design pattern, for the same reason."
msgstr ""
#: ../Doc/faq/programming.rst:291
msgid "What are the \"best practices\" for using import in a module?"
msgstr ""
#: ../Doc/faq/programming.rst:293
msgid ""
"In general, don't use ``from modulename import *``. Doing so clutters "
"the importer's namespace, and makes it much harder for linters to detect "
"undefined names."
msgstr ""
#: ../Doc/faq/programming.rst:297
msgid ""
"Import modules at the top of a file. Doing so makes it clear what other "
"modules your code requires and avoids questions of whether the module "
"name is in scope. Using one import per line makes it easy to add and "
"delete module imports, but using multiple imports per line uses less "
"screen space."
msgstr ""
#: ../Doc/faq/programming.rst:302
msgid "It's good practice if you import modules in the following order:"
msgstr ""
#: ../Doc/faq/programming.rst:304
msgid "standard library modules -- e.g. ``sys``, ``os``, ``getopt``, ``re``"
msgstr ""
#: ../Doc/faq/programming.rst:305
msgid ""
"third-party library modules (anything installed in Python's site-packages"
" directory) -- e.g. mx.DateTime, ZODB, PIL.Image, etc."
msgstr ""
#: ../Doc/faq/programming.rst:307
msgid "locally-developed modules"
msgstr ""
#: ../Doc/faq/programming.rst:309
msgid ""
"It is sometimes necessary to move imports to a function or class to avoid"
" problems with circular imports. Gordon McMillan says:"
msgstr ""
#: ../Doc/faq/programming.rst:312
msgid ""
"Circular imports are fine where both modules use the \"import <module>\" "
"form of import. They fail when the 2nd module wants to grab a name out "
"of the first (\"from module import name\") and the import is at the top "
"level. That's because names in the 1st are not yet available, because "
"the first module is busy importing the 2nd."
msgstr ""
#: ../Doc/faq/programming.rst:318
msgid ""
"In this case, if the second module is only used in one function, then the"
" import can easily be moved into that function. By the time the import "
"is called, the first module will have finished initializing, and the "
"second module can do its import."
msgstr ""
#: ../Doc/faq/programming.rst:323
msgid ""
"It may also be necessary to move imports out of the top level of code if "
"some of the modules are platform-specific. In that case, it may not even"
" be possible to import all of the modules at the top of the file. In "
"this case, importing the correct modules in the corresponding platform-"
"specific code is a good option."
msgstr ""
#: ../Doc/faq/programming.rst:328
msgid ""
"Only move imports into a local scope, such as inside a function "
"definition, if it's necessary to solve a problem such as avoiding a "
"circular import or are trying to reduce the initialization time of a "
"module. This technique is especially helpful if many of the imports are "
"unnecessary depending on how the program executes. You may also want to "
"move imports into a function if the modules are only ever used in that "
"function. Note that loading a module the first time may be expensive "
"because of the one time initialization of the module, but loading a "
"module multiple times is virtually free, costing only a couple of "
"dictionary lookups. Even if the module name has gone out of scope, the "
"module is probably available in :data:`sys.modules`."
msgstr ""
#: ../Doc/faq/programming.rst:341
msgid "Why are default values shared between objects?"
msgstr ""
#: ../Doc/faq/programming.rst:343
msgid ""
"This type of bug commonly bites neophyte programmers. Consider this "
"function::"
msgstr ""
#: ../Doc/faq/programming.rst:350
msgid ""
"The first time you call this function, ``mydict`` contains a single item."
" The second time, ``mydict`` contains two items because when ``foo()`` "
"begins executing, ``mydict`` starts out with an item already in it."
msgstr ""
#: ../Doc/faq/programming.rst:354
msgid ""
"It is often expected that a function call creates new objects for default"
" values. This is not what happens. Default values are created exactly "
"once, when the function is defined. If that object is changed, like the "
"dictionary in this example, subsequent calls to the function will refer "
"to this changed object."
msgstr ""
#: ../Doc/faq/programming.rst:359
msgid ""
"By definition, immutable objects such as numbers, strings, tuples, and "
"``None``, are safe from change. Changes to mutable objects such as "
"dictionaries, lists, and class instances can lead to confusion."
msgstr ""
#: ../Doc/faq/programming.rst:363
msgid ""
"Because of this feature, it is good programming practice to not use "
"mutable objects as default values. Instead, use ``None`` as the default "
"value and inside the function, check if the parameter is ``None`` and "
"create a new list/dictionary/whatever if it is. For example, don't "
"write::"
msgstr ""
#: ../Doc/faq/programming.rst:371
msgid "but::"
msgstr ""
#: ../Doc/faq/programming.rst:377
msgid ""
"This feature can be useful. When you have a function that's time-"
"consuming to compute, a common technique is to cache the parameters and "
"the resulting value of each call to the function, and return the cached "
"value if the same value is requested again. This is called "
"\"memoizing\", and can be implemented like this::"
msgstr ""
#: ../Doc/faq/programming.rst:392
msgid ""
"You could use a global variable containing a dictionary instead of the "
"default value; it's a matter of taste."
msgstr ""
#: ../Doc/faq/programming.rst:397
msgid ""
"How can I pass optional or keyword parameters from one function to "
"another?"
msgstr ""
#: ../Doc/faq/programming.rst:399
msgid ""
"Collect the arguments using the ``*`` and ``**`` specifiers in the "
"function's parameter list; this gives you the positional arguments as a "
"tuple and the keyword arguments as a dictionary. You can then pass these"
" arguments when calling another function by using ``*`` and ``**``::"
msgstr ""
#: ../Doc/faq/programming.rst:418
msgid "What is the difference between arguments and parameters?"
msgstr ""
#: ../Doc/faq/programming.rst:420
msgid ""
":term:`Parameters <parameter>` are defined by the names that appear in a "
"function definition, whereas :term:`arguments <argument>` are the values "
"actually passed to a function when calling it. Parameters define what "
"types of arguments a function can accept. For example, given the "
"function definition::"
msgstr ""
#: ../Doc/faq/programming.rst:428
msgid ""
"*foo*, *bar* and *kwargs* are parameters of ``func``. However, when "
"calling ``func``, for example::"
msgstr ""
#: ../Doc/faq/programming.rst:433
msgid "the values ``42``, ``314``, and ``somevar`` are arguments."
msgstr ""
#: ../Doc/faq/programming.rst:437
msgid "Why did changing list 'y' also change list 'x'?"
msgstr ""
#: ../Doc/faq/programming.rst:439
msgid "If you wrote code like::"
msgstr ""
#: ../Doc/faq/programming.rst:449
msgid ""
"you might be wondering why appending an element to ``y`` changed ``x`` "
"too."
msgstr ""
#: ../Doc/faq/programming.rst:451
msgid "There are two factors that produce this result:"
msgstr ""
#: ../Doc/faq/programming.rst:453
msgid ""
"Variables are simply names that refer to objects. Doing ``y = x`` "
"doesn't create a copy of the list -- it creates a new variable ``y`` that"
" refers to the same object ``x`` refers to. This means that there is "
"only one object (the list), and both ``x`` and ``y`` refer to it."
msgstr ""
#: ../Doc/faq/programming.rst:457
msgid "Lists are :term:`mutable`, which means that you can change their content."
msgstr ""
#: ../Doc/faq/programming.rst:459
msgid ""
"After the call to :meth:`~list.append`, the content of the mutable object"
" has changed from ``[]`` to ``[10]``. Since both the variables refer to "
"the same object, using either name accesses the modified value ``[10]``."
msgstr ""
#: ../Doc/faq/programming.rst:463
msgid "If we instead assign an immutable object to ``x``::"
msgstr ""
#: ../Doc/faq/programming.rst:473
msgid ""
"we can see that in this case ``x`` and ``y`` are not equal anymore. This"
" is because integers are :term:`immutable`, and when we do ``x = x + 1`` "
"we are not mutating the int ``5`` by incrementing its value; instead, we "
"are creating a new object (the int ``6``) and assigning it to ``x`` (that"
" is, changing which object ``x`` refers to). After this assignment we "
"have two objects (the ints ``6`` and ``5``) and two variables that refer "
"to them (``x`` now refers to ``6`` but ``y`` still refers to ``5``)."
msgstr ""
#: ../Doc/faq/programming.rst:481
msgid ""
"Some operations (for example ``y.append(10)`` and ``y.sort()``) mutate "
"the object, whereas superficially similar operations (for example ``y = y"
" + [10]`` and ``sorted(y)``) create a new object. In general in Python "
"(and in all cases in the standard library) a method that mutates an "
"object will return ``None`` to help avoid getting the two types of "
"operations confused. So if you mistakenly write ``y.sort()`` thinking it"
" will give you a sorted copy of ``y``, you'll instead end up with "
"``None``, which will likely cause your program to generate an easily "
"diagnosed error."
msgstr ""
#: ../Doc/faq/programming.rst:490
msgid ""
"However, there is one class of operations where the same operation "
"sometimes has different behaviors with different types: the augmented "
"assignment operators. For example, ``+=`` mutates lists but not tuples "
"or ints (``a_list += [1, 2, 3]`` is equivalent to ``a_list.extend([1, 2, "
"3])`` and mutates ``a_list``, whereas ``some_tuple += (1, 2, 3)`` and "
"``some_int += 1`` create new objects)."
msgstr ""
#: ../Doc/faq/programming.rst:497
msgid "In other words:"
msgstr ""
#: ../Doc/faq/programming.rst:499
msgid ""
"If we have a mutable object (:class:`list`, :class:`dict`, :class:`set`, "
"etc.), we can use some specific operations to mutate it and all the "
"variables that refer to it will see the change."
msgstr ""
#: ../Doc/faq/programming.rst:502
msgid ""
"If we have an immutable object (:class:`str`, :class:`int`, "
":class:`tuple`, etc.), all the variables that refer to it will always see"
" the same value, but operations that transform that value into a new "
"value always return a new object."
msgstr ""
#: ../Doc/faq/programming.rst:507
msgid ""
"If you want to know if two variables refer to the same object or not, you"
" can use the :keyword:`is` operator, or the built-in function :func:`id`."
msgstr ""
#: ../Doc/faq/programming.rst:512
msgid "How do I write a function with output parameters (call by reference)?"
msgstr ""
#: ../Doc/faq/programming.rst:514
msgid ""
"Remember that arguments are passed by assignment in Python. Since "
"assignment just creates references to objects, there's no alias between "
"an argument name in the caller and callee, and so no call-by-reference "
"per se. You can achieve the desired effect in a number of ways."
msgstr ""
#: ../Doc/faq/programming.rst:519
msgid "By returning a tuple of the results::"
msgstr ""
#: ../Doc/faq/programming.rst:530
msgid "This is almost always the clearest solution."
msgstr ""
#: ../Doc/faq/programming.rst:532
msgid ""
"By using global variables. This isn't thread-safe, and is not "
"recommended."
msgstr ""
#: ../Doc/faq/programming.rst:534
msgid "By passing a mutable (changeable in-place) object::"
msgstr ""
#: ../Doc/faq/programming.rst:544
msgid "By passing in a dictionary that gets mutated::"
msgstr ""
#: ../Doc/faq/programming.rst:554
msgid "Or bundle up values in a class instance::"
msgstr ""
#: ../Doc/faq/programming.rst:570
msgid "There's almost never a good reason to get this complicated."
msgstr ""
#: ../Doc/faq/programming.rst:572
msgid "Your best choice is to return a tuple containing the multiple results."
msgstr ""
#: ../Doc/faq/programming.rst:576
msgid "How do you make a higher order function in Python?"
msgstr ""
#: ../Doc/faq/programming.rst:578
msgid ""
"You have two choices: you can use nested scopes or you can use callable "
"objects. For example, suppose you wanted to define ``linear(a,b)`` which "
"returns a function ``f(x)`` that computes the value ``a*x+b``. Using "
"nested scopes::"
msgstr ""
#: ../Doc/faq/programming.rst:587
msgid "Or using a callable object::"
msgstr ""
#: ../Doc/faq/programming.rst:597
msgid "In both cases, ::"
msgstr ""
#: ../Doc/faq/programming.rst:601
msgid "gives a callable object where ``taxes(10e6) == 0.3 * 10e6 + 2``."
msgstr ""
#: ../Doc/faq/programming.rst:603
msgid ""
"The callable object approach has the disadvantage that it is a bit slower"
" and results in slightly longer code. However, note that a collection of"
" callables can share their signature via inheritance::"
msgstr ""
#: ../Doc/faq/programming.rst:612
msgid "Object can encapsulate state for several methods::"
msgstr ""
#: ../Doc/faq/programming.rst:630
msgid ""
"Here ``inc()``, ``dec()`` and ``reset()`` act like functions which share "
"the same counting variable."
msgstr ""
#: ../Doc/faq/programming.rst:635
msgid "How do I copy an object in Python?"
msgstr ""
#: ../Doc/faq/programming.rst:637
msgid ""
"In general, try :func:`copy.copy` or :func:`copy.deepcopy` for the "
"general case. Not all objects can be copied, but most can."
msgstr ""
#: ../Doc/faq/programming.rst:640
msgid ""
"Some objects can be copied more easily. Dictionaries have a "
":meth:`~dict.copy` method::"
msgstr ""
#: ../Doc/faq/programming.rst:645
msgid "Sequences can be copied by slicing::"
msgstr ""
#: ../Doc/faq/programming.rst:651
msgid "How can I find the methods or attributes of an object?"
msgstr ""
#: ../Doc/faq/programming.rst:653
msgid ""
"For an instance x of a user-defined class, ``dir(x)`` returns an "
"alphabetized list of the names containing the instance attributes and "
"methods and attributes defined by its class."
msgstr ""
#: ../Doc/faq/programming.rst:659
msgid "How can my code discover the name of an object?"
msgstr ""
#: ../Doc/faq/programming.rst:661
msgid ""
"Generally speaking, it can't, because objects don't really have names. "
"Essentially, assignment always binds a name to a value; The same is true "
"of ``def`` and ``class`` statements, but in that case the value is a "
"callable. Consider the following code::"
msgstr ""
#: ../Doc/faq/programming.rst:677
msgid ""
"Arguably the class has a name: even though it is bound to two names and "
"invoked through the name B the created instance is still reported as an "
"instance of class A. However, it is impossible to say whether the "
"instance's name is a or b, since both names are bound to the same value."
msgstr ""
#: ../Doc/faq/programming.rst:682
msgid ""
"Generally speaking it should not be necessary for your code to \"know the"
" names\" of particular values. Unless you are deliberately writing "
"introspective programs, this is usually an indication that a change of "
"approach might be beneficial."
msgstr ""
#: ../Doc/faq/programming.rst:687
msgid ""
"In comp.lang.python, Fredrik Lundh once gave an excellent analogy in "
"answer to this question:"
msgstr ""
#: ../Doc/faq/programming.rst:690
msgid ""
"The same way as you get the name of that cat you found on your porch: the"
" cat (object) itself cannot tell you its name, and it doesn't really care"
" -- so the only way to find out what it's called is to ask all your "
"neighbours (namespaces) if it's their cat (object)..."
msgstr ""
#: ../Doc/faq/programming.rst:695
msgid ""
"....and don't be surprised if you'll find that it's known by many names, "
"or no name at all!"
msgstr ""
#: ../Doc/faq/programming.rst:700
msgid "What's up with the comma operator's precedence?"
msgstr ""
#: ../Doc/faq/programming.rst:702
msgid "Comma is not an operator in Python. Consider this session::"
msgstr ""
#: ../Doc/faq/programming.rst:707
msgid ""
"Since the comma is not an operator, but a separator between expressions "
"the above is evaluated as if you had entered::"
msgstr ""
#: ../Doc/faq/programming.rst:712
msgid "not::"
msgstr ""
#: ../Doc/faq/programming.rst:716
msgid ""
"The same is true of the various assignment operators (``=``, ``+=`` etc)."
" They are not truly operators but syntactic delimiters in assignment "
"statements."
msgstr ""
#: ../Doc/faq/programming.rst:721
msgid "Is there an equivalent of C's \"?:\" ternary operator?"
msgstr ""
#: ../Doc/faq/programming.rst:723
msgid "Yes, there is. The syntax is as follows::"
msgstr ""
#: ../Doc/faq/programming.rst:730
msgid ""
"Before this syntax was introduced in Python 2.5, a common idiom was to "
"use logical operators::"
msgstr ""
#: ../Doc/faq/programming.rst:735
msgid ""
"However, this idiom is unsafe, as it can give wrong results when "
"*on_true* has a false boolean value. Therefore, it is always better to "
"use the ``... if ... else ...`` form."
msgstr ""
#: ../Doc/faq/programming.rst:741
msgid "Is it possible to write obfuscated one-liners in Python?"
msgstr ""
#: ../Doc/faq/programming.rst:743
msgid ""
"Yes. Usually this is done by nesting :keyword:`lambda` within "
":keyword:`!lambda`. See the following three examples, due to Ulf "
"Bartelt::"
msgstr ""
#: ../Doc/faq/programming.rst:770
msgid "Don't try this at home, kids!"
msgstr ""
#: ../Doc/faq/programming.rst:776
msgid "What does the slash(/) in the parameter list of a function mean?"
msgstr ""
#: ../Doc/faq/programming.rst:778
msgid ""
"A slash in the argument list of a function denotes that the parameters "
"prior to it are positional-only. Positional-only parameters are the ones"
" without an externally-usable name. Upon calling a function that accepts"
" positional-only parameters, arguments are mapped to parameters based "
"solely on their position. For example, :func:`pow` is a function that "
"accepts positional-only parameters. Its documentation looks like this::"
msgstr ""
#: ../Doc/faq/programming.rst:794
msgid ""
"The slash at the end of the parameter list means that all three "
"parameters are positional-only. Thus, calling :func:`pow` with keyword "
"aguments would lead to an error::"
msgstr ""
#: ../Doc/faq/programming.rst:803
msgid ""
"Note that as of this writing this is only documentational and no valid "
"syntax in Python, although there is :pep:`570`, which proposes a syntax "
"for position-only parameters in Python."
msgstr ""
#: ../Doc/faq/programming.rst:809
msgid "Numbers and strings"
msgstr ""
#: ../Doc/faq/programming.rst:812
msgid "How do I specify hexadecimal and octal integers?"
msgstr ""
#: ../Doc/faq/programming.rst:814
msgid ""
"To specify an octal digit, precede the octal value with a zero, and then "
"a lower or uppercase \"o\". For example, to set the variable \"a\" to "
"the octal value \"10\" (8 in decimal), type::"
msgstr ""
#: ../Doc/faq/programming.rst:822
msgid ""
"Hexadecimal is just as easy. Simply precede the hexadecimal number with "
"a zero, and then a lower or uppercase \"x\". Hexadecimal digits can be "
"specified in lower or uppercase. For example, in the Python "
"interpreter::"
msgstr ""
#: ../Doc/faq/programming.rst:835
msgid "Why does -22 // 10 return -3?"
msgstr ""
#: ../Doc/faq/programming.rst:837
msgid ""
"It's primarily driven by the desire that ``i % j`` have the same sign as "
"``j``. If you want that, and also want::"
msgstr ""
#: ../Doc/faq/programming.rst:842
msgid ""
"then integer division has to return the floor. C also requires that "
"identity to hold, and then compilers that truncate ``i // j`` need to "
"make ``i % j`` have the same sign as ``i``."
msgstr ""
#: ../Doc/faq/programming.rst:846
msgid ""
"There are few real use cases for ``i % j`` when ``j`` is negative. When "
"``j`` is positive, there are many, and in virtually all of them it's more"
" useful for ``i % j`` to be ``>= 0``. If the clock says 10 now, what did"
" it say 200 hours ago? ``-190 % 12 == 2`` is useful; ``-190 % 12 == "
"-10`` is a bug waiting to bite."
msgstr ""
#: ../Doc/faq/programming.rst:854
msgid "How do I convert a string to a number?"
msgstr ""
#: ../Doc/faq/programming.rst:856
msgid ""
"For integers, use the built-in :func:`int` type constructor, e.g. "
"``int('144') == 144``. Similarly, :func:`float` converts to floating-"
"point, e.g. ``float('144') == 144.0``."
msgstr ""
#: ../Doc/faq/programming.rst:860
msgid ""
"By default, these interpret the number as decimal, so that ``int('0144') "
"== 144`` and ``int('0x144')`` raises :exc:`ValueError`. ``int(string, "
"base)`` takes the base to convert from as a second optional argument, so "
"``int('0x144', 16) == 324``. If the base is specified as 0, the number "
"is interpreted using Python's rules: a leading '0o' indicates octal, and "
"'0x' indicates a hex number."
msgstr ""
#: ../Doc/faq/programming.rst:866
msgid ""
"Do not use the built-in function :func:`eval` if all you need is to "
"convert strings to numbers. :func:`eval` will be significantly slower "
"and it presents a security risk: someone could pass you a Python "
"expression that might have unwanted side effects. For example, someone "
"could pass ``__import__('os').system(\"rm -rf $HOME\")`` which would "
"erase your home directory."
msgstr ""
#: ../Doc/faq/programming.rst:873
msgid ""
":func:`eval` also has the effect of interpreting numbers as Python "
"expressions, so that e.g. ``eval('09')`` gives a syntax error because "
"Python does not allow leading '0' in a decimal number (except '0')."
msgstr ""
#: ../Doc/faq/programming.rst:879
msgid "How do I convert a number to a string?"
msgstr ""
#: ../Doc/faq/programming.rst:881