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#
SOME DESCRIPTIVE TITLE.
#
Copyright (C) 2001-2021, Python Software Foundation
#
This file is distributed under the same license as the Python package.
#
FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#
#
Translators:
#
Maciej Olko <maciej.olko@gmail.com>, 2021
#
Stefan Ocetkiewicz <stefan.ocetkiewicz@gmail.com>, 2022
#
Krzysztof Abramowicz, 2022
#
#,
fuzzy
msgid ""
msgstr ""
"
Project-Id-Version
:
Python 3.8\n
"
"
Report-Msgid-Bugs-To
:
\n
"
"
POT-Creation-Date
:
2021-04-29 17:15+0000\n
"
"
PO-Revision-Date
:
2020-05-30 11:53+0000\n
"
"
Last-Translator
:
Krzysztof Abramowicz, 2022\n
"
"
Language-Team
:
Polish (https://www.transifex.com/python-doc/teams/5390/pl/)\n
"
"
MIME-Version
:
1.0\n
"
"
Content-Type
:
text/plain; charset=UTF-8\n
"
"
Content-Transfer-Encoding
:
8bit\n
"
"
Language
:
pl\n
"
"
Plural-Forms
:
nplurals=4; plural=(n==1 ? 0 : (n%10>=2 && n%10<=4) &&
"
"
(n%100<12 || n%100>14) ? 1 : n!=1 && (n%10>=0 && n%10<=1) || (n%10>=5 &&
"
"
n%10<=9) || (n%100>=12 && n%100<=14) ? 2 : 3);\n
"
msgid
"Programming FAQ"
msgstr
"FAQ - programowanie"
msgid
"Contents"
msgstr
"Zawarto"
msgid
"General Questions"
msgstr
"Pytania oglne"
msgid
""
"Is there a source code level debugger with breakpoints, single-stepping, "
"etc.?"
msgstr
""
"Czy istnieje debugger kodu rdowego z obsug punktw przerwania, krokowym "
"wykonywaniem akcji itp.?"
msgid
"Yes."
msgstr
"Tak"
msgid
""
"Several debuggers for Python are described below, and the built-in function :"
"func:`breakpoint` allows you to drop into any of them."
msgstr
""
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
""
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
""
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 "
"`pywin32 <https://github.com/mhammond/pywin32>`_ project and as a part of "
"the `ActivePython <https://www.activestate.com/products/python/>`_ "
"distribution."
msgstr
""
msgid
""
"`Eric <http://eric-ide.python-projects.org/>`_ is an IDE built on PyQt and "
"the Scintilla editing component."
msgstr
""
msgid
""
"`trepan3k <https://github.com/rocky/python3-trepan/>`_ is a gdb-like "
"debugger."
msgstr
""
msgid
""
"`Visual Studio Code <https://code.visualstudio.com/>`_ is an IDE with "
"debugging tools that integrates with version-control software."
msgstr
""
msgid
""
"There are a number of commercial Python IDEs that include graphical "
"debuggers. They include:"
msgstr
""
msgid
"`Wing IDE <https://wingware.com/>`_"
msgstr
""
msgid
"`Komodo IDE <https://www.activestate.com/products/komodo-ide/>`_"
msgstr
""
msgid
"`PyCharm <https://www.jetbrains.com/pycharm/>`_"
msgstr
""
msgid
"Are there tools to help find bugs or perform static analysis?"
msgstr
""
msgid
""
"`Pylint <https://www.pylint.org/>`_ and `Pyflakes <https://github.com/PyCQA/"
"pyflakes>`_ do basic checking that will help you catch bugs sooner."
msgstr
""
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
""
msgid
"How can I create a stand-alone binary from a Python script?"
msgstr
""
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
""
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
""
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
""
msgid
""
"Obviously, freeze requires a C compiler. There are several other utilities "
"which don't:"
msgstr
""
msgid
"`py2exe <http://www.py2exe.org/>`_ for Windows binaries"
msgstr
""
msgid
""
"`py2app <https://github.com/ronaldoussoren/py2app>`_ for Mac OS X binaries"
msgstr
""
msgid
""
"`cx_Freeze <https://cx-freeze.readthedocs.io/en/latest/>`_ for cross-"
"platform binaries"
msgstr
""
msgid
"Are there coding standards or a style guide for Python programs?"
msgstr
""
msgid
""
"Yes. The coding style required for standard library modules is documented "
"as :pep:`8`."
msgstr
""
msgid
"Core Language"
msgstr
"Rdze jzyka"
msgid
"Why am I getting an UnboundLocalError when the variable has a value?"
msgstr
""
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
""
msgid
"This code:"
msgstr
"Ten kod:"
msgid
"works, but this code:"
msgstr
"dziaa, ale ten kod:"
msgid
"results in an UnboundLocalError:"
msgstr
"wywoa wyjtek UnboundLocalError:"
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
""
msgid
""
"In the example above you can access the outer scope variable by declaring it "
"global:"
msgstr
""
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
""
msgid
""
"You can do a similar thing in a nested scope using the :keyword:`nonlocal` "
"keyword:"
msgstr
""
msgid
"What are the rules for local and global variables in Python?"
msgstr
""
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
""
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
""
msgid
""
"Why do lambdas defined in a loop with different values all return the same "
"result?"
msgstr
""
msgid
""
"Assume you use a for loop to define a few different lambdas (or even plain "
"functions), e.g.::"
msgstr
""
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
""
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
""
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
""
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
""
msgid
""
"Note that this behaviour is not peculiar to lambdas, but applies to regular "
"functions too."
msgstr
""
msgid
"How do I share global variables across modules?"
msgstr
""
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
""
msgid
"config.py::"
msgstr
"config.py::"
msgid
"mod.py::"
msgstr
"mod.py::"
msgid
"main.py::"
msgstr
"main.py::"
msgid
""
"Note that using a module is also the basis for implementing the Singleton "
"design pattern, for the same reason."
msgstr
""
msgid
"What are the
\"
best practices
\"
for using import in a module?"
msgstr
""
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
""
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
""
msgid
"It's good practice if you import modules in the following order:"
msgstr
""
msgid
"standard library modules -- e.g. ``sys``, ``os``, ``getopt``, ``re``"
msgstr
""
msgid
""
"third-party library modules (anything installed in Python's site-packages "
"directory) -- e.g. mx.DateTime, ZODB, PIL.Image, etc."
msgstr
""
msgid
"locally-developed modules"
msgstr
""
msgid
""
"It is sometimes necessary to move imports to a function or class to avoid "
"problems with circular imports. Gordon McMillan says:"
msgstr
""
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
""
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
""
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
""
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
""
msgid
"Why are default values shared between objects?"
msgstr
""
msgid
""
"This type of bug commonly bites neophyte programmers. Consider this "
"function::"
msgstr
""
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
""
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
""
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
""
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
""
msgid
"but::"
msgstr
"ale:"
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
""
msgid
""
"You could use a global variable containing a dictionary instead of the "
"default value; it's a matter of taste."
msgstr
""
msgid
""
"How can I pass optional or keyword parameters from one function to another?"
msgstr
""
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
""
msgid
"What is the difference between arguments and parameters?"
msgstr
"Jaka jest rnica pomidzy argumentami a parametrami?"
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
""
msgid
""
"*foo*, *bar* and *kwargs* are parameters of ``func``. However, when calling "
"``func``, for example::"
msgstr
""
msgid
"the values ``42``, ``314``, and ``somevar`` are arguments."
msgstr
""
msgid
"Why did changing list 'y' also change list 'x'?"
msgstr
""
msgid
"If you wrote code like::"
msgstr
""
msgid
""
"you might be wondering why appending an element to ``y`` changed ``x`` too."
msgstr
""
msgid
"There are two factors that produce this result:"
msgstr
""
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
""
msgid
""
"Lists are :term:`mutable`, which means that you can change their content."
msgstr
""
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
""
msgid
"If we instead assign an immutable object to ``x``::"
msgstr
""
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
""
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
""
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
""
msgid
"In other words:"
msgstr
"Innymi sowami:"
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
""
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
""
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
""
msgid
"How do I write a function with output parameters (call by reference)?"
msgstr
""
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
""
msgid
"By returning a tuple of the results::"
msgstr
""
msgid
"This is almost always the clearest solution."
msgstr
""
msgid
""
"By using global variables. This isn't thread-safe, and is not recommended."
msgstr
""
msgid
"By passing a mutable (changeable in-place) object::"
msgstr
""
msgid
"By passing in a dictionary that gets mutated::"
msgstr
""
msgid
"Or bundle up values in a class instance::"
msgstr
""
msgid
"There's almost never a good reason to get this complicated."
msgstr
""
msgid
"Your best choice is to return a tuple containing the multiple results."
msgstr
""
msgid
"How do you make a higher order function in Python?"
msgstr
""
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
""
msgid
"Or using a callable object::"
msgstr
""
msgid
"In both cases, ::"
msgstr
"W obydwu przypadkach, ::"
msgid
"gives a callable object where ``taxes(10e6) == 0.3 * 10e6 + 2``."
msgstr
""
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
""
msgid
"Object can encapsulate state for several methods::"
msgstr
""
msgid
""
"Here ``inc()``, ``dec()`` and ``reset()`` act like functions which share the "
"same counting variable."
msgstr
""
msgid
"How do I copy an object in Python?"
msgstr
"Jak mog skopiowa obiekt w Pythonie?"
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
""
msgid
""
"Some objects can be copied more easily. Dictionaries have a :meth:`~dict."
"copy` method::"
msgstr
""
msgid
"Sequences can be copied by slicing::"
msgstr
""
msgid
"How can I find the methods or attributes of an object?"
msgstr
""
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
""
msgid
"How can my code discover the name of an object?"
msgstr
""
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
""
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
""
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
""
msgid
""
"In comp.lang.python, Fredrik Lundh once gave an excellent analogy in answer "
"to this question:"
msgstr
""
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
""
msgid
""
"....and don't be surprised if you'll find that it's known by many names, or "
"no name at all!"
msgstr
""
msgid
"What's up with the comma operator's precedence?"
msgstr
""
msgid
"Comma is not an operator in Python. Consider this session::"
msgstr
""
msgid
""
"Since the comma is not an operator, but a separator between expressions the "
"above is evaluated as if you had entered::"
msgstr
""
msgid
"not::"
msgstr
""
msgid
""
"The same is true of the various assignment operators (``=``, ``+=`` etc). "
"They are not truly operators but syntactic delimiters in assignment "
"statements."
msgstr
""
msgid
"Is there an equivalent of C's
\"
?:
\"
ternary operator?"
msgstr
""
msgid
"Yes, there is. The syntax is as follows::"
msgstr
""
msgid
""
"Before this syntax was introduced in Python 2.5, a common idiom was to use "
"logical operators::"
msgstr
""
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
""
msgid
"Is it possible to write obfuscated one-liners in Python?"
msgstr
"Czy w Pythonie da si napisa pokrcony jednolinijkowy kod?"
msgid
""
"Yes. Usually this is done by nesting :keyword:`lambda` within :keyword:`!"
"lambda`. See the following three examples, due to Ulf Bartelt::"
msgstr
""
"Oczywicie. Zwykle odbywa si to poprzez zagniedenie :keyword:`lambda` w :"
"keyword:`!lambda`. Zobacz nastpujce trzy przykady, autorstwo: Ulf "
"Bartelt::"
msgid
"Don't try this at home, kids!"
msgstr
"Nie prbujcie tego w domu, dzieciaki!"
msgid
"What does the slash(/) in the parameter list of a function mean?"
msgstr
""
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:`divmod` is a function that accepts positional-"
"only parameters. Its documentation looks like this::"
msgstr
""
msgid
""
"The slash at the end of the parameter list means that both parameters are "
"positional-only. Thus, calling :func:`divmod` with keyword arguments would "
"lead to an error::"
msgstr
""
msgid
"Numbers and strings"
msgstr
"Numery i cigi znakw"
msgid
"How do I specify hexadecimal and octal integers?"
msgstr
""
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
""
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
""
msgid
"Why does -22 // 10 return -3?"
msgstr
"Dlaczego -22 // 10 zwraca -3?"
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
""
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
""
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
""
msgid
"How do I convert a string to a number?"
msgstr
"Jak skonwertowa cig znakw na liczb?"
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
""
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
""
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
""
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
""
msgid
"How do I convert a number to a string?"
msgstr
"Jak skonwertowa liczb na cig znakw?"
msgid
""
"To convert, e.g., the number 144 to the string '144', use the built-in type "
"constructor :func:`str`. If you want a hexadecimal or octal representation, "
"use the built-in functions :func:`hex` or :func:`oct`. For fancy "
"formatting, see the :ref:`f-strings` and :ref:`formatstrings` sections, e.g. "
"``
\"
{:04d}
\"
.format(144)`` yields ``'0144'`` and ``
\"
{:.3f}
\"
."
"format(1.0/3.0)`` yields ``'0.333'``."
msgstr
""
msgid
"How do I modify a string in place?"
msgstr
"Jak zmodyfikowa cig znakw
\"
w miejscu
\"
?"
msgid
""
"You can't, because strings are immutable. In most situations, you should "
"simply construct a new string from the various parts you want to assemble it "
"from. However, if you need an object with the ability to modify in-place "
"unicode data, try using an :class:`io.StringIO` object or the :mod:`array` "
"module::"
msgstr
""
msgid
"How do I use strings to call functions/methods?"
msgstr
""
msgid
"There are various techniques."
msgstr
""
msgid
""
"The best is to use a dictionary that maps strings to functions. The primary "
"advantage of this technique is that the strings do not need to match the "
"names of the functions. This is also the primary technique used to emulate "
"a case construct::"
msgstr
""
msgid
"Use the built-in function :func:`getattr`::"
msgstr
""
msgid
""
"Note that :func:`getattr` works on any object, including classes, class "
"instances, modules, and so on."
msgstr
""
msgid
"This is used in several places in the standard library, like this::"
msgstr
""
msgid
"Use :func:`locals` or :func:`eval` to resolve the function name::"
msgstr
""
msgid
""
"Note: Using :func:`eval` is slow and dangerous. If you don't have absolute "
"control over the contents of the string, someone could pass a string that "
"resulted in an arbitrary function being executed."
msgstr
""
msgid
""
"Is there an equivalent to Perl's chomp() for removing trailing newlines from "
"strings?"
msgstr
""
msgid
""
"You can use ``S.rstrip(
\"\\
r
\\
n
\"
)`` to remove all occurrences of any line "
"terminator from the end of the string ``S`` without removing other trailing "
"whitespace. If the string ``S`` represents more than one line, with several "
"empty lines at the end, the line terminators for all the blank lines will be "
"removed::"
msgstr
""
msgid
""
"Since this is typically only desired when reading text one line at a time, "
"using ``S.rstrip()`` this way works well."
msgstr
""
msgid
"Is there a scanf() or sscanf() equivalent?"
msgstr
""
msgid
"Not as such."
msgstr
""
msgid
""
"For simple input parsing, the easiest approach is usually to split the line "
"into whitespace-delimited words using the :meth:`~str.split` method of "
"string objects and then convert decimal strings to numeric values using :"
"func:`int` or :func:`float`. ``split()`` supports an optional
\"
sep
\"
"
"parameter which is useful if the line uses something other than whitespace "
"as a separator."
msgstr
""
msgid
""
"For more complicated input parsing, regular expressions are more powerful "
"than C's :c:func:`sscanf` and better suited for the task."
msgstr
""
msgid
"What does 'UnicodeDecodeError' or 'UnicodeEncodeError' error mean?"
msgstr
""
msgid
"See the :ref:`unicode-howto`."
msgstr
""
msgid
"Performance"
msgstr
"Wydajno"
msgid
"My program is too slow. How do I speed it up?"
msgstr
"Mj program jest za wolny. Jak mog go przyspieszy?"
msgid
""
"That's a tough one, in general. First, here are a list of things to "
"remember before diving further:"
msgstr
""
msgid
""
"Performance characteristics vary across Python implementations. This FAQ "
"focuses on :term:`CPython`."
msgstr
""
msgid
""
"Behaviour can vary across operating systems, especially when talking about I/"
"O or multi-threading."
msgstr
""
msgid
""
"You should always find the hot spots in your program *before* attempting to "
"optimize any code (see the :mod:`profile` module)."
msgstr
""
msgid
""
"Writing benchmark scripts will allow you to iterate quickly when searching "
"for improvements (see the :mod:`timeit` module)."
msgstr
""
msgid
""
"It is highly recommended to have good code coverage (through unit testing or "
"any other technique) before potentially introducing regressions hidden in "
"sophisticated optimizations."
msgstr
""
msgid
""
"That being said, there are many tricks to speed up Python code. Here are "
"some general principles which go a long way towards reaching acceptable "
"performance levels:"
msgstr
""
msgid
""
"Making your algorithms faster (or changing to faster ones) can yield much "
"larger benefits than trying to sprinkle micro-optimization tricks all over "
"your code."
msgstr
""
msgid
""
"Use the right data structures. Study documentation for the :ref:`bltin-"
"types` and the :mod:`collections` module."
msgstr
""
msgid
""
"When the standard library provides a primitive for doing something, it is "
"likely (although not guaranteed) to be faster than any alternative you may "
"come up with. This is doubly true for primitives written in C, such as "
"builtins and some extension types. For example, be sure to use either the :"
"meth:`list.sort` built-in method or the related :func:`sorted` function to "
"do sorting (and see the :ref:`sortinghowto` for examples of moderately "
"advanced usage)."
msgstr
""
msgid
""
"Abstractions tend to create indirections and force the interpreter to work "
"more. If the levels of indirection outweigh the amount of useful work done, "
"your program will be slower. You should avoid excessive abstraction, "
"especially under the form of tiny functions or methods (which are also often "
"detrimental to readability)."
msgstr
""
msgid
""
"If you have reached the limit of what pure Python can allow, there are tools "
"to take you further away. For example, `Cython <http://cython.org>`_ can "
"compile a slightly modified version of Python code into a C extension, and "
"can be used on many different platforms. Cython can take advantage of "
"compilation (and optional type annotations) to make your code significantly "
"faster than when interpreted. If you are confident in your C programming "
"skills, you can also :ref:`write a C extension module <extending-index>` "
"yourself."
msgstr
""
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