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GeezerVison is showing github.com — python-docs-ru/library/__main__.po at 3.14 · python/python-docs-ru Expand file tree/ Copy path__main__.poMore file actions 474 lines (402 loc) · 13.8 KB / Copy path__main__.poFile metadata and controls474 lines (402 loc) · 13.8 KB 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 # SOME DESCRIPTIVE TITLE. # Copyright (C) 2001 Python Software Foundation # This file is distributed under the same license as the Python package. # FIRST AUTHOR <EMAIL@ADDRESS>, YEAR. # # Translators: # python-doc bot, 2025 # #, fuzzy msgid "" msgstr "" "Project-Id-Version: Python 3.15\n" "Report-Msgid-Bugs-To: \n" "POT-Creation-Date: 2026-11-01 18:39+0000\n" "PO-Revision-Date: 2025-09-16 00:00+0000\n" "Last-Translator: python-doc bot, 2025\n" "Language-Team: Russian (https://app.transifex.com/python-doc/teams/5390/" "ru/)\n" "MIME-Version: 1.0\n" "Content-Type: text/plain; charset=UTF-8\n" "Content-Transfer-Encoding: 8bit\n" "Language: ru\n" "Plural-Forms: nplurals=4; plural=(n%10==1 && n%100!=11 ? 0 : n%10>=2 && " "n%10<=4 && (n%100<12 || n%100>14) ? 1 : n%10==0 || (n%10>=5 && n%10<=9) || " "(n%100>=11 && n%100<=14)? 2 : 3);\n" msgid ":mod:`!__main__` --- Top-level code environment" msgstr "" msgid "" "In Python, the special name ``__main__`` is used for two important " "constructs:" msgstr "" msgid "" "the name of the top-level environment of the program, which can be checked " "using the ``__name__ == '__main__'`` expression; and" msgstr "" msgid "the ``__main__.py`` file in Python packages." msgstr "" msgid "" "Both of these mechanisms are related to Python modules; how users interact " "with them and how they interact with each other. They are explained in " "detail below. If you're new to Python modules, see the tutorial " "section :ref:`tut-modules` for an introduction." msgstr "" msgid "``__name__ == '__main__'``" msgstr "" msgid "" "When a Python module or package is imported, ``__name__`` is set to the " "module's name. Usually, this is the name of the Python file itself without " "the ``.py`` extension::" msgstr "" msgid "" ">>> import configparser\n" ">>> configparser.__name__\n" "'configparser'" msgstr "" msgid "" "If the file is part of a package, ``__name__`` will also include the parent " "package's path::" msgstr "" msgid "" ">>> from concurrent.futures import process\n" ">>> process.__name__\n" "'concurrent.futures.process'" msgstr "" msgid "" "However, if the module is executed in the top-level code environment, its " "``__name__`` is set to the string ``'__main__'``." msgstr "" msgid "What is the \"top-level code environment\"?" msgstr "" msgid "" "``__main__`` is the name of the environment where top-level code is run. " "\"Top-level code\" is the first user-specified Python module that starts " "running. It's \"top-level\" because it imports all other modules that the " "program needs. Sometimes \"top-level code\" is called an *entry point* to " "the application." msgstr "" msgid "The top-level code environment can be:" msgstr "" msgid "the scope of an interactive prompt::" msgstr "" msgid "" ">>> __name__\n" "'__main__'" msgstr "" msgid "the Python module passed to the Python interpreter as a file argument:" msgstr "" msgid "" "$ python helloworld.py\n" "Hello, world!" msgstr "" msgid "" "the Python module or package passed to the Python interpreter with " "the :option:`-m` argument:" msgstr "" msgid "" "$ python -m tarfile\n" "usage: tarfile.py [-h] [-v] (...)" msgstr "" msgid "Python code read by the Python interpreter from standard input:" msgstr "" msgid "" "$ echo \"import this\" | python\n" "The Zen of Python, by Tim Peters\n" "\n" "Beautiful is better than ugly.\n" "Explicit is better than implicit.\n" "..." msgstr "" msgid "" "Python code passed to the Python interpreter with the :option:`-c` argument:" msgstr "" msgid "" "$ python -c \"import this\"\n" "The Zen of Python, by Tim Peters\n" "\n" "Beautiful is better than ugly.\n" "Explicit is better than implicit.\n" "..." msgstr "" msgid "" "In each of these situations, the top-level module's ``__name__`` is set to " "``'__main__'``." msgstr "" msgid "" "As a result, a module can discover whether or not it is running in the top-" "level environment by checking its own ``__name__``, which allows a common " "idiom for conditionally executing code when the module is not initialized " "from an import statement::" msgstr "" msgid "" "if __name__ == '__main__':\n" " # Execute when the module is not initialized from an import statement.\n" " ..." msgstr "" msgid "" "For a more detailed look at how ``__name__`` is set in all situations, see " "the tutorial section :ref:`tut-modules`." msgstr "" msgid "Idiomatic Usage" msgstr "" msgid "" "Some modules contain code that is intended for script use only, like parsing " "command-line arguments or fetching data from standard input. If a module " "like this was imported from a different module, for example to unit test it, " "the script code would unintentionally execute as well." msgstr "" msgid "" "This is where using the ``if __name__ == '__main__'`` code block comes in " "handy. Code within this block won't run unless the module is executed in the " "top-level environment." msgstr "" msgid "" "Putting as few statements as possible in the block below ``if __name__ == " "'__main__'`` can improve code clarity and correctness. Most often, a " "function named ``main`` encapsulates the program's primary behavior::" msgstr "" msgid "" "# echo.py\n" "\n" "import shlex\n" "import sys\n" "\n" "def echo(phrase: str) -> None:\n" " \"\"\"A dummy wrapper around print.\"\"\"\n" " # for demonstration purposes, you can imagine that there is some\n" " # valuable and reusable logic inside this function\n" " print(phrase)\n" "\n" "def main() -> int:\n" " \"\"\"Echo the input arguments to standard output\"\"\"\n" " phrase = shlex.join(sys.argv)\n" " echo(phrase)\n" " return 0\n" "\n" "if __name__ == '__main__':\n" " sys.exit(main()) # next section explains the use of sys.exit" msgstr "" msgid "" "Note that if the module didn't encapsulate code inside the ``main`` function " "but instead put it directly within the ``if __name__ == '__main__'`` block, " "the ``phrase`` variable would be global to the entire module. This is error-" "prone as other functions within the module could be unintentionally using " "the global variable instead of a local name. A ``main`` function solves " "this problem." msgstr "" msgid "" "Using a ``main`` function has the added benefit of the ``echo`` function " "itself being isolated and importable elsewhere. When ``echo.py`` is " "imported, the ``echo`` and ``main`` functions will be defined, but neither " "of them will be called, because ``__name__ != '__main__'``." msgstr "" msgid "Packaging Considerations" msgstr "" msgid "" "``main`` functions are often used to create command-line tools by specifying " "them as entry points for console scripts. When this is done, `pip <https://" "pip.pypa.io/>`_ inserts the function call into a template script, where the " "return value of ``main`` is passed into :func:`sys.exit`. For example::" msgstr "" msgid "sys.exit(main())" msgstr "" msgid "" "Since the call to ``main`` is wrapped in :func:`sys.exit`, the expectation " "is that your function will return some value acceptable as an input " "to :func:`sys.exit`; typically, an integer or ``None`` (which is implicitly " "returned if your function does not have a return statement)." msgstr "" msgid "" "By proactively following this convention ourselves, our module will have the " "same behavior when run directly (i.e. ``python echo.py``) as it will have if " "we later package it as a console script entry-point in a pip-installable " "package." msgstr "" msgid "" "In particular, be careful about returning strings from your ``main`` " "function. :func:`sys.exit` will interpret a string argument as a failure " "message, so your program will have an exit code of ``1``, indicating " "failure, and the string will be written to :data:`sys.stderr`. The " "``echo.py`` example from earlier exemplifies using the ``sys.exit(main())`` " "convention." msgstr "" msgid "" "`Python Packaging User Guide <https://packaging.python.org/>`_ contains a " "collection of tutorials and references on how to distribute and install " "Python packages with modern tools." msgstr "" msgid "``__main__.py`` in Python Packages" msgstr "" msgid "" "If you are not familiar with Python packages, see section :ref:`tut-" "packages` of the tutorial. Most commonly, the ``__main__.py`` file is used " "to provide a command-line interface for a package. Consider the following " "hypothetical package, \"bandclass\":" msgstr "" msgid "" "bandclass\n" " ├── __init__.py\n" " ├── __main__.py\n" " └── student.py" msgstr "" msgid "" "``__main__.py`` will be executed when the package itself is invoked directly " "from the command line using the :option:`-m` flag. For example:" msgstr "" msgid "$ python -m bandclass" msgstr "" msgid "" "This command will cause ``__main__.py`` to run. How you utilize this " "mechanism will depend on the nature of the package you are writing, but in " "this hypothetical case, it might make sense to allow the teacher to search " "for students::" msgstr "" msgid "" "# bandclass/__main__.py\n" "\n" "import sys\n" "from .student import search_students\n" "\n" "student_name = sys.argv[1] if len(sys.argv) >= 2 else ''\n" "print(f'Found student: {search_students(student_name)}')" msgstr "" msgid "" "Note that ``from .student import search_students`` is an example of a " "relative import. This import style can be used when referencing modules " "within a package. For more details, see :ref:`intra-package-references` in " "the :ref:`tut-modules` section of the tutorial." msgstr "" msgid "" "The content of ``__main__.py`` typically isn't fenced with an ``if __name__ " "== '__main__'`` block. Instead, those files are kept short and import " "functions to execute from other modules. Those other modules can then be " "easily unit-tested and are properly reusable." msgstr "" msgid "" "If used, an ``if __name__ == '__main__'`` block will still work as expected " "for a ``__main__.py`` file within a package, because its ``__name__`` " "attribute will include the package's path if imported::" msgstr "" msgid "" ">>> import asyncio.__main__\n" ">>> asyncio.__main__.__name__\n" "'asyncio.__main__'" msgstr "" msgid "" "This won't work for ``__main__.py`` files in the root directory of a " "``.zip`` file though. Hence, for consistency, a minimal ``__main__.py`` " "without a ``__name__`` check is preferred." msgstr "" msgid "" "See :mod:`venv` for an example of a package with a minimal ``__main__.py`` " "in the standard library. It doesn't contain a ``if __name__ == '__main__'`` " "block. You can invoke it with ``python -m venv [directory]``." msgstr "" msgid "" "See :mod:`runpy` for more details on the :option:`-m` flag to the " "interpreter executable." msgstr "" msgid "" "See :mod:`zipapp` for how to run applications packaged as *.zip* files. In " "this case Python looks for a ``__main__.py`` file in the root directory of " "the archive." msgstr "" msgid "``import __main__``" msgstr "" msgid "" "Regardless of which module a Python program was started with, other modules " "running within that same program can import the top-level environment's " "scope (:term:`namespace`) by importing the ``__main__`` module. This " "doesn't import a ``__main__.py`` file but rather whichever module that " "received the special name ``'__main__'``." msgstr "" msgid "Here is an example module that consumes the ``__main__`` namespace::" msgstr "" msgid "" "# namely.py\n" "\n" "import __main__\n" "\n" "def did_user_define_their_name():\n" " return 'my_name' in dir(__main__)\n" "\n" "def print_user_name():\n" " if not did_user_define_their_name():\n" " raise ValueError('Define the variable `my_name`!')\n" "\n" " print(__main__.my_name)" msgstr "" msgid "Example usage of this module could be as follows::" msgstr "" msgid "" "# start.py\n" "\n" "import sys\n" "\n" "from namely import print_user_name\n" "\n" "# my_name = \"Dinsdale\"\n" "\n" "def main():\n" " try:\n" " print_user_name()\n" " except ValueError as ve:\n" " return str(ve)\n" "\n" "if __name__ == \"__main__\":\n" " sys.exit(main())" msgstr "" msgid "Now, if we started our program, the result would look like this:" msgstr "" msgid "" "$ python start.py\n" "Define the variable `my_name`!" msgstr "" msgid "" "The exit code of the program would be 1, indicating an error. Uncommenting " "the line with ``my_name = \"Dinsdale\"`` fixes the program and now it exits " "with status code 0, indicating success:" msgstr "" msgid "" "$ python start.py\n" "Dinsdale" msgstr "" msgid "" "Note that importing ``__main__`` doesn't cause any issues with " "unintentionally running top-level code meant for script use which is put in " "the ``if __name__ == \"__main__\"`` block of the ``start`` module. Why does " "this work?" msgstr "" msgid "" "Python inserts an empty ``__main__`` module in :data:`sys.modules` at " "interpreter startup, and populates it by running top-level code. In our " "example this is the ``start`` module which runs line by line and imports " "``namely``. In turn, ``namely`` imports ``__main__`` (which is really " "``start``). That's an import cycle! Fortunately, since the partially " "populated ``__main__`` module is present in :data:`sys.modules`, Python " "passes that to ``namely``. See :ref:`Special considerations for __main__ " "<import-dunder-main>` in the import system's reference for details on how " "this works." msgstr "" msgid "" "The Python REPL is another example of a \"top-level environment\", so " "anything defined in the REPL becomes part of the ``__main__`` scope::" msgstr "" msgid "" ">>> import namely\n" ">>> namely.did_user_define_their_name()\n" "False\n" ">>> namely.print_user_name()\n" "Traceback (most recent call last):\n" "...\n" "ValueError: Define the variable `my_name`!\n" ">>> my_name = 'Jabberwocky'\n" ">>> namely.did_user_define_their_name()\n" "True\n" ">>> namely.print_user_name()\n" "Jabberwocky" msgstr "" msgid "" "The ``__main__`` scope is used in the implementation of :mod:`pdb` " "and :mod:`rlcompleter`." msgstr "" |
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