Group items tagged

I hope this article encourages you to think about your command line programs in a different light, and to treat them as first class objects. Using inheritance to share code is so common in other areas of development that it is hardly given a second thought in most cases. As has been shown with the SQLiteAppBase programs, the same technique can be just as powerful when applied to building command line programs, saving development time and testing effort as a result. CommandLineApp has been used as the foundation for dozens of types of programs, and could be just what you need the next time you have to write a new command line program.

I didn’t want to make a new build tool. Honestly. The main reason that I created Paver is...

One of the main difficulties I've had using parser generators has been the difficulty of figuring out why a grammar didn't work. Fixing shift-reduce and reduce-reduce conflicts seemed like voodoo to me, and though I slightly understand better how to fix such things now it's still a different mode of thinking that I don't want to try to get into when I just want to parse something simple. PyMeta uses a variation on the Parsing Expression Grammar (PEG) approach to parsing. The chief consequence of this is there's no possibility of ambiguity in a parse: a successful parse will yield exactly one result, and you can trace the control flow through the grammar to figure out how it got there.

On Mon, May 5, 2008 at 8:22 PM, Reckoner <recko...@gmail.com> wrote: > is there a unit step (heaviside) function in sympy? > I need to work a conditional into a symbolic expression. We have sign which is basically the same thing:

I'm declaring this one to be the winner! (Not that my opinion counts for anythin, but I'm just impressed: a1, b1 = zip(*ab) (or a1, b1 = apply(zip,ab)?) BTW: this process isn't 100% inverse. It has the side effect of turning lists or strings (non-tuple sequences) into tuples, if they are supplied as the original sequences.

Charming Python: Using state machinesAlgorithms and programming approaches in Python

Charming Python: SimPy simplifies complex models

To attempt to explain it in the simplest terms, a continuation is a representation, at a particular point in a program, of everything the program is capable of doing subsequently. A continuation is a potential that depends on initial conditions. Rather than loop in a traditional way, it is possible to invoke the same continuation recursively with different initial conditions. One broad claim I have read is that continuations, in a theoretical sense, are more fundamental and underlie every other control structure. Don't worry if these ideas cause your brain to melt; that is a normal reaction.

Stackless Python is an alternative implementation of Python created by independent developer Christian Tismer. He started with the conventional Python language processor managed by the language's inventor, Guido van Rossum, and patched his own Stackless invention in place of a small but central part of Python's internals. Stackless Python is the result. This article introduces Tismer's technology and its significance. In future articles, you'll be able to read about how to make your own start at programming Stackless Python, as well as the prospects for a merger between Stackless and the main Python distribution.

Note that it's more rebust to run methods on the public IPython api.I.e. do ip = ipshell.api and then ip.magic('px import os')You can explore the api interactively by playing with _ip object.

In our last article on compression we showed you how to demonstrate run time encoding in Python. In this article we'll show you how to implement another kind of compression, Huffman encoding, which is useful when dealing with small sets of items, such as character strings.

Testoob is an advanced unit testing framework for Python. It integrates effortlessly with existing PyUnit (module ‘unittest’) test suites.

On Sat, 15 Dec 2001 17:53:49 -0800 (PST), David Brady <daves_spam_dodging_account at yahoo.com> wrote : >More win32all questions... is it possible to get the >handle of the window that currently has the focus? >win32gui.GetActiveWindow() fails because I'm looking >for a window outside the process of my Python script. E:\>python ActivePython 2.1.1, build 212 (ActiveState) Python 2.1.1 (#20, Jul 26 2001, 11:38:51) [MSC 32 bit (Intel)] on win32 Type "copyright", "credits" or "license" for more information. >>> import win32gui >>> import time >>> for x in range(10): ... time.sleep(1) ... print x, win32gui.GetWindowText(win32gui.GetForegroundWindow()) ... 0 cmd - python 1 cmd - python 2 (Untitled) * SciTE 3 (Untitled) * SciTE 4 ActivePython Documentation 5 ActivePython Documentation 6 PythonWin 7 PythonWin 8 PythonWin