### 导航 - [索引](../genindex.xhtml "总目录") - [模块](../py-modindex.xhtml "Python 模块索引") | - [下一页](compileall.xhtml "compileall --- Byte-compile Python libraries") | - [上一页](pyclbr.xhtml "pyclbr --- Python class browser support") | -  - [Python](https://www.python.org/) » - zh\_CN 3.7.3 [文档](../index.xhtml) » - [Python 标准库](index.xhtml) » - [Python 语言服务](language.xhtml) » - $('.inline-search').show(0); | # [`py_compile`](#module-py_compile "py_compile: Generate byte-code files from Python source files.") --- Compile Python source files **Source code:** [Lib/py\_compile.py](https://github.com/python/cpython/tree/3.7/Lib/py_compile.py) \[https://github.com/python/cpython/tree/3.7/Lib/py\_compile.py\] - - - - - - The [`py_compile`](#module-py_compile "py_compile: Generate byte-code files from Python source files.") module provides a function to generate a byte-code file from a source file, and another function used when the module source file is invoked as a script. Though not often needed, this function can be useful when installing modules for shared use, especially if some of the users may not have permission to write the byte-code cache files in the directory containing the source code. *exception* `py_compile.``PyCompileError`Exception raised when an error occurs while attempting to compile the file. `py_compile.``compile`(*file*, *cfile=None*, *dfile=None*, *doraise=False*, *optimize=-1*, *invalidation\_mode=PycInvalidationMode.TIMESTAMP*)Compile a source file to byte-code and write out the byte-code cache file. The source code is loaded from the file named *file*. The byte-code is written to *cfile*, which defaults to the [**PEP 3147**](https://www.python.org/dev/peps/pep-3147) \[https://www.python.org/dev/peps/pep-3147\]/[**PEP 488**](https://www.python.org/dev/peps/pep-0488) \[https://www.python.org/dev/peps/pep-0488\] path, ending in `.pyc`. For example, if *file* is `/foo/bar/baz.py` *cfile* will default to `/foo/bar/__pycache__/baz.cpython-32.pyc` for Python 3.2. If *dfile* is specified, it is used as the name of the source file in error messages when instead of *file*. If *doraise* is true, a [`PyCompileError`](#py_compile.PyCompileError "py_compile.PyCompileError") is raised when an error is encountered while compiling *file*. If *doraise* is false (the default), an error string is written to `sys.stderr`, but no exception is raised. This function returns the path to byte-compiled file, i.e. whatever *cfile* value was used. If the path that *cfile* becomes (either explicitly specified or computed) is a symlink or non-regular file, [`FileExistsError`](exceptions.xhtml#FileExistsError "FileExistsError") will be raised. This is to act as a warning that import will turn those paths into regular files if it is allowed to write byte-compiled files to those paths. This is a side-effect of import using file renaming to place the final byte-compiled file into place to prevent concurrent file writing issues. *optimize* controls the optimization level and is passed to the built-in [`compile()`](functions.xhtml#compile "compile") function. The default of `-1` selects the optimization level of the current interpreter. *invalidation\_mode* should be a member of the [`PycInvalidationMode`](#py_compile.PycInvalidationMode "py_compile.PycInvalidationMode")enum and controls how the generated bytecode cache is invalidated at runtime. The default is [`PycInvalidationMode.CHECKED_HASH`](#py_compile.PycInvalidationMode.CHECKED_HASH "py_compile.PycInvalidationMode.CHECKED_HASH") if the `SOURCE_DATE_EPOCH` environment variable is set, otherwise the default is [`PycInvalidationMode.TIMESTAMP`](#py_compile.PycInvalidationMode.TIMESTAMP "py_compile.PycInvalidationMode.TIMESTAMP"). 在 3.2 版更改: Changed default value of *cfile* to be [**PEP 3147**](https://www.python.org/dev/peps/pep-3147) \[https://www.python.org/dev/peps/pep-3147\]-compliant. Previous default was *file* + `'c'` (`'o'` if optimization was enabled). Also added the *optimize* parameter. 在 3.4 版更改: Changed code to use [`importlib`](importlib.xhtml#module-importlib "importlib: The implementation of the import machinery.") for the byte-code cache file writing. This means file creation/writing semantics now match what [`importlib`](importlib.xhtml#module-importlib "importlib: The implementation of the import machinery.")does, e.g. permissions, write-and-move semantics, etc. Also added the caveat that [`FileExistsError`](exceptions.xhtml#FileExistsError "FileExistsError") is raised if *cfile* is a symlink or non-regular file. 在 3.7 版更改: The *invalidation\_mode* parameter was added as specified in [**PEP 552**](https://www.python.org/dev/peps/pep-0552) \[https://www.python.org/dev/peps/pep-0552\]. If the `SOURCE_DATE_EPOCH` environment variable is set, *invalidation\_mode* will be forced to [`PycInvalidationMode.CHECKED_HASH`](#py_compile.PycInvalidationMode.CHECKED_HASH "py_compile.PycInvalidationMode.CHECKED_HASH"). 在 3.7.2 版更改: The `SOURCE_DATE_EPOCH` environment variable no longer overrides the value of the *invalidation\_mode* argument, and determines its default value instead. *class* `py_compile.``PycInvalidationMode`A enumeration of possible methods the interpreter can use to determine whether a bytecode file is up to date with a source file. The `.pyc` file indicates the desired invalidation mode in its header. See [已缓存字节码的失效](../reference/import.xhtml#pyc-invalidation) for more information on how Python invalidates `.pyc` files at runtime. 3\.7 新版功能. `TIMESTAMP`The `.pyc` file includes the timestamp and size of the source file, which Python will compare against the metadata of the source file at runtime to determine if the `.pyc` file needs to be regenerated. `CHECKED_HASH`The `.pyc` file includes a hash of the source file content, which Python will compare against the source at runtime to determine if the `.pyc`file needs to be regenerated. `UNCHECKED_HASH`Like [`CHECKED_HASH`](#py_compile.PycInvalidationMode.CHECKED_HASH "py_compile.PycInvalidationMode.CHECKED_HASH"), the `.pyc` file includes a hash of the source file content. However, Python will at runtime assume the `.pyc` file is up to date and not validate the `.pyc` against the source file at all. This option is useful when the `.pycs` are kept up to date by some system external to Python like a build system. `py_compile.``main`(*args=None*)Compile several source files. The files named in *args* (or on the command line, if *args* is `None`) are compiled and the resulting byte-code is cached in the normal manner. This function does not search a directory structure to locate source files; it only compiles files named explicitly. If `'-'` is the only parameter in args, the list of files is taken from standard input. 在 3.2 版更改: Added support for `'-'`. When this module is run as a script, the [`main()`](#py_compile.main "py_compile.main") is used to compile all the files named on the command line. The exit status is nonzero if one of the files could not be compiled. 参见 Module [`compileall`](compileall.xhtml#module-compileall "compileall: Tools for byte-compiling all Python source files in a directory tree.")Utilities to compile all Python source files in a directory tree. ### 导航 - [索引](../genindex.xhtml "总目录") - [模块](../py-modindex.xhtml "Python 模块索引") | - [下一页](compileall.xhtml "compileall --- Byte-compile Python libraries") | - [上一页](pyclbr.xhtml "pyclbr --- Python class browser support") | -  - [Python](https://www.python.org/) » - zh\_CN 3.7.3 [文档](../index.xhtml) » - [Python 标准库](index.xhtml) » - [Python 语言服务](language.xhtml) » - $('.inline-search').show(0); | © [版权所有](../copyright.xhtml) 2001-2019, Python Software Foundation. Python 软件基金会是一个非盈利组织。 [请捐助。](https://www.python.org/psf/donations/) 最后更新于 5月 21, 2019. [发现了问题](../bugs.xhtml)？ 使用[Sphinx](http://sphinx.pocoo.org/)1.8.4 创建。