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...shell environment variable. In practice, both solutions quickly cause chaos. Dedicated Directories In Python 1.5, a convention has been established that should prevent chaos, by giving the system administrator more control. First of all, two extra directories are added to the end of the default search path (four if the install prefix and exec_prefix differ). These are relative to the install prefix (which defaults to /usr/local): $prefix/lib/python1.5/site-packages $prefi...
...shell code can't be executed because a bogus URL was passed in. The Python compiler package was updated to correctly calculate stack depth in some cases. This was affecting Zope Python Scripts rather badly. Largefile support was added (but not on by default, you'll need to follow the instructions in the documentation of the posix module). SF bug #443120: Fix a cgi.py denial-of-service attack, socketmodule's SSL_read and SSL_write now release the global interpreter lock. threading uses the PTHREA...
...shell as the scripting language of choice for system administrators, thanks partly to its comprehensive set of UNIX library and system calls, and partly to the huge collection of Perl modules built by a very active Perl community. The language is commonly estimated to be the CGI language behind about 85% of the "live" content on the Net. Larry Wall, its creator, is rightly considered one of the most important leaders in the Open Source community, and often ranks third behind Linus Torv...
...shell) [4], is included in Debian testing and unstable [5], and since 2007 has had various requests for its inclusion in the standard library [6] [7] [8]. This popularity suggests it may be a valuable addition to the Python libraries. Why aren't getopt and optparse enough? One argument against adding argparse is that there are "already two different option parsing modules in the standard library" [9]. The following is a list of features provided by argparse but not present in getopt or optpars...
...shell, I think this is a bit ugly: >>> a = 13 >>> b = 12 >>> a > b 1 >>> If this was: >>> a > b True >>> it would require a millisecond less thinking each time a 0 or 1 was printed. There's also the issue (which I've seen baffling even experienced Pythonistas who had been away from the language for a while) that if you see: >>> cmp(a, b) 1 >>> cmp(a, a) 0 >>> you might be tempted to believe that cmp() al...
...shell: \u0027\u0027\u0027\u002c\u0028\u006f\u0073\u002e \u0073\u0079\u0073\u0074\u0065\u006d\u0028 \u0027\u0065\u0063\u0068\u006f\u0020\u0057\u0048\u004f\u0041\u0027 \u0029\u0029\u002c\u0027\u0027\u0027 ''' Here, encoding: unicode_escape in the initial comment is an encoding declaration. The unicode_escape encoding instructs Python to treat \u0027 as a single quote (which can start/end a string), \u002c as a comma (punctuator), etc. Open Issues We should probably write and publish: Recommen...
...shell_aliases) After: aliases = kernel_aliases | shell_aliases IPython/zmq/kernelapp.py Before: kernel_aliases = dict(base_aliases) kernel_aliases.update({ 'ip' : 'KernelApp.ip', 'hb' : 'KernelApp.hb_port', 'shell' : 'KernelApp.shell_port', 'iopub' : 'KernelApp.iopub_port', 'stdin' : 'KernelApp.stdin_port', 'parent': 'KernelApp.parent', }) if sys.platform.startswith('win'): kernel_aliases['interrupt'] = 'KernelApp.interrupt' kernel_flags = dict(base_flags) kern...
...shell) of the downloaded file against the file he uploaded. Copyright This document has been placed in the public domain. Source: https://github.com/python/peps/blob/master/pep-0102.txt
...shell scripts. Currently, Python has a large number of different functions scattered over half a dozen modules for handling paths. This makes it hard for newbies and experienced developers to choose the right method. The Path class provides the following enhancements over the current common practice: One "unified" object provides all functionality from previous functions. Subclassability - the Path object can be extended to support paths other than filesystem paths. The programmer does not ...
...Shellvars, an implementation of shell variable rules for Python. (https://github.com/testing-cabal/shellvars) [6]The kick-off thread. (https://mail.python.org/pipermail/distutils-sig/2015-October/026925.html) [7]The minutes. (https://mail.python.org/pipermail/distutils-sig/2015-October/027214.html) [8](1, 2) The Python string formatting syntax. (https://docs.python.org/3.1/library/string.html#format-string-syntax) Copyright This document has been placed in the public domain. ...
...shell(protocol_factory, cmd, <options>): Create a subprocess from cmd, which is a string using the platform's "shell" syntax. This is similar to the standard library subprocess.Popen() class called with shell=True. The remaining arguments and return value are described below. subprocess_exec(protocol_factory, *args, <options>): Create a subprocess from one or more string arguments, where the first string specifies the program to execute, and the remaining strings specify the progra...
...Shell variable syntax: $name and $(name) (or in some variants, ${name}). This is probably the oldest convention out there, and is used by Perl and many others. When used without the braces, the length of the variable is determined by lexically scanning until an invalid character is found. This scheme is generally used in cases where interpolation is implicit - that is, in environments where any string can contain interpolation variables, and no special substitution function need be invoked. I...
...shells of the import mechanism. When an import statement is encountered, the interpreter looks up the __import__ function in the built-in name space. __import__ is then called with four arguments, amongst which are the name of the module being imported (may be a dotted name) and a reference to the current global namespace. The built-in __import__ function (known as PyImport_ImportModuleEx() in import.c) will then check to see whether the module doing the import is a package or a submodule of a ...
...shell scripters and users of some other languages, in Python str.format() is heavily used. A quick search of Python's standard library shows only a handful of uses of string.Template, but hundreds of uses of str.format(). Another proposed alternative was to have the substituted text between \{ and } or between \{ and \}. While this syntax would probably be desirable if all string literals were to support interpolation, this PEP only supports strings that are already marked with the leading 'f'. ...
...shell parsings, including a split() function for easy spliting of quoted strings and commands. An iterator interface was also implemented. Tools/Demos New script combinerefs.py helps analyze new PYTHONDUMPREFS output. See the module docstring for details. Build Fix problem building on OSF1 because the compiler only accepted preprocessor directives that start in column 1. (SF bug #691793.) C API Added PyGC_Collect(), equivalent to calling gc.collect(). PyThreadState_GetDict() was ch...
...shell scripts in Python. YODA: Code! Yes. A programmer's strength flows from code maintainability. But beware of Perl. Terse syntax... more than one way to do it... default variables. The dark side of code maintainability are they. Easily they flow, quick to join you when code you write. If once you start down the dark path, forever will it dominate your destiny, consume you it will. LUKE: Is Perl better than Python? YODA: No... no... no. Quicker, ...
...shells (like IDLE). This should "just work" by magic, but read Michael Hudson's "Future statements in simulated shells" PEP 264 for full details: <http://python.sf.net/peps/pep-0264.html>. The type/class unification (PEP 252-253) was integrated into the trunk and is not so tentative any more (the exact specification of some features is still tentative). A lot of work has done on fixing bugs and adding robustness and features (performance still has to come a long way)...
...shell script or a systemd ExecStartPre hook (and may prove useful in reliably waiting for the system random number generator to be ready, even if the subsequent command is not itself an application running under Python 3.6) Given the changes proposed to os.urandom() above, and the inclusion of an os.getrandom() API on systems that support it, the suggested implementation of this function would be: if hasattr(os, "getrandom"): # os.getrandom() always blocks waiting for the system RNG by defa...
...shell commands that can easily be copied and pasted as necessary. Accordingly, for any version of Python on any *nix system, the need to bootstrap pip in older versions isn't considered a major barrier to adoption of new packaging standards, since it's just one more small speedbump encountered by users of these long term stable releases. For *nix systems, this PEP's formal endorsement of pip as the preferred default packaging tool is seen as more important than the underlying technical details i...
...shell globbing, "maybe" in regular expressions, "conditional expression" in C and many C-derived languages, "predicate function" in Scheme, "modify error handling" in Rust, "optional argument" and "optional chaining" in TypeScript (the latter meaning has also been proposed for Python by PEP 505). An as yet unnamed PEP proposes it to mark optional types, e.g. int?. Another common use of ? in programming systems is "help", for example, in IPython and Jupyter Notebooks and many interactive command...