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diff --git a/Doc/library/packaging.util.rst b/Doc/library/packaging.util.rst new file mode 100644 index 0000000..b95d5b5 --- /dev/null +++ b/Doc/library/packaging.util.rst @@ -0,0 +1,186 @@ +:mod:`packaging.util` --- Miscellaneous utility functions +========================================================= + +.. module:: packaging.util + :synopsis: Miscellaneous utility functions. + + +This module contains various helpers for the other modules. + +.. XXX a number of functions are missing, but the module may be split first + (it's ginormous right now, some things could go to compat for example) + +.. function:: get_platform() + + Return a string that identifies the current platform. This is used mainly to + distinguish platform-specific build directories and platform-specific built + distributions. Typically includes the OS name and version and the + architecture (as supplied by 'os.uname()'), although the exact information + included depends on the OS; e.g. for IRIX the architecture isn't particularly + important (IRIX only runs on SGI hardware), but for Linux the kernel version + isn't particularly important. + + Examples of returned values: + + * ``linux-i586`` + * ``linux-alpha`` + * ``solaris-2.6-sun4u`` + * ``irix-5.3`` + * ``irix64-6.2`` + + For non-POSIX platforms, currently just returns ``sys.platform``. + + For Mac OS X systems the OS version reflects the minimal version on which + binaries will run (that is, the value of ``MACOSX_DEPLOYMENT_TARGET`` + during the build of Python), not the OS version of the current system. + + For universal binary builds on Mac OS X the architecture value reflects + the univeral binary status instead of the architecture of the current + processor. For 32-bit universal binaries the architecture is ``fat``, + for 64-bit universal binaries the architecture is ``fat64``, and + for 4-way universal binaries the architecture is ``universal``. Starting + from Python 2.7 and Python 3.2 the architecture ``fat3`` is used for + a 3-way universal build (ppc, i386, x86_64) and ``intel`` is used for + a univeral build with the i386 and x86_64 architectures + + Examples of returned values on Mac OS X: + + * ``macosx-10.3-ppc`` + + * ``macosx-10.3-fat`` + + * ``macosx-10.5-universal`` + + * ``macosx-10.6-intel`` + + .. XXX reinvention of platform module? + + +.. function:: convert_path(pathname) + + Return 'pathname' as a name that will work on the native filesystem, i.e. + split it on '/' and put it back together again using the current directory + separator. Needed because filenames in the setup script are always supplied + in Unix style, and have to be converted to the local convention before we + can actually use them in the filesystem. Raises :exc:`ValueError` on + non-Unix-ish systems if *pathname* either starts or ends with a slash. + + +.. function:: change_root(new_root, pathname) + + Return *pathname* with *new_root* prepended. If *pathname* is relative, this + is equivalent to ``os.path.join(new_root,pathname)`` Otherwise, it requires + making *pathname* relative and then joining the two, which is tricky on + DOS/Windows. + + +.. function:: check_environ() + + Ensure that 'os.environ' has all the environment variables we guarantee that + users can use in config files, command-line options, etc. Currently this + includes: + + * :envvar:`HOME` - user's home directory (Unix only) + * :envvar:`PLAT` - description of the current platform, including hardware + and OS (see :func:`get_platform`) + + +.. function:: find_executable(executable, path=None) + + Search the path for a given executable name. + + +.. function:: subst_vars(s, local_vars) + + Perform shell/Perl-style variable substitution on *s*. Every occurrence of + ``$`` followed by a name is considered a variable, and variable is + substituted by the value found in the *local_vars* dictionary, or in + ``os.environ`` if it's not in *local_vars*. *os.environ* is first + checked/augmented to guarantee that it contains certain values: see + :func:`check_environ`. Raise :exc:`ValueError` for any variables not found + in either *local_vars* or ``os.environ``. + + Note that this is not a fully-fledged string interpolation function. A valid + ``$variable`` can consist only of upper and lower case letters, numbers and + an underscore. No { } or ( ) style quoting is available. + + +.. function:: split_quoted(s) + + Split a string up according to Unix shell-like rules for quotes and + backslashes. In short: words are delimited by spaces, as long as those spaces + are not escaped by a backslash, or inside a quoted string. Single and double + quotes are equivalent, and the quote characters can be backslash-escaped. + The backslash is stripped from any two-character escape sequence, leaving + only the escaped character. The quote characters are stripped from any + quoted string. Returns a list of words. + + .. TODO Should probably be moved into the standard library. + + +.. function:: execute(func, args[, msg=None, verbose=0, dry_run=0]) + + Perform some action that affects the outside world (for instance, writing to + the filesystem). Such actions are special because they are disabled by the + *dry_run* flag. This method takes care of all that bureaucracy for you; + all you have to do is supply the function to call and an argument tuple for + it (to embody the "external action" being performed), and an optional message + to print. + + +.. function:: newer(source, target) + + Return true if *source* exists and is more recently modified than *target*, + or if *source* exists and *target* doesn't. Return false if both exist and + *target* is the same age or newer than *source*. Raise + :exc:`PackagingFileError` if *source* does not exist. + + +.. function:: strtobool(val) + + Convert a string representation of truth to true (1) or false (0). + + True values are ``y``, ``yes``, ``t``, ``true``, ``on`` and ``1``; false + values are ``n``, ``no``, ``f``, ``false``, ``off`` and ``0``. Raises + :exc:`ValueError` if *val* is anything else. + +.. TODO Add :term: markup to bytecode when merging into the stdlib + +.. function:: byte_compile(py_files[, optimize=0, force=0, prefix=None, base_dir=None, verbose=1, dry_run=0, direct=None]) + + Byte-compile a collection of Python source files to either :file:`.pyc` or + :file:`.pyo` files in the same directory. *py_files* is a list of files to + compile; any files that don't end in :file:`.py` are silently skipped. + *optimize* must be one of the following: + + * ``0`` - don't optimize (generate :file:`.pyc`) + * ``1`` - normal optimization (like ``python -O``) + * ``2`` - extra optimization (like ``python -OO``) + + If *force* is true, all files are recompiled regardless of timestamps. + + The source filename encoded in each bytecode file defaults to the filenames + listed in *py_files*; you can modify these with *prefix* and *basedir*. + *prefix* is a string that will be stripped off of each source filename, and + *base_dir* is a directory name that will be prepended (after *prefix* is + stripped). You can supply either or both (or neither) of *prefix* and + *base_dir*, as you wish. + + If *dry_run* is true, doesn't actually do anything that would affect the + filesystem. + + Byte-compilation is either done directly in this interpreter process with the + standard :mod:`py_compile` module, or indirectly by writing a temporary + script and executing it. Normally, you should let :func:`byte_compile` + figure out to use direct compilation or not (see the source for details). + The *direct* flag is used by the script generated in indirect mode; unless + you know what you're doing, leave it set to ``None``. + + +.. function:: rfc822_escape(header) + + Return a version of *header* escaped for inclusion in an :rfc:`822` header, by + ensuring there are 8 spaces space after each newline. Note that it does no + other modification of the string. + + .. TODO this _can_ be replaced |