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Python Converted To JavaScript, Executed In-Browser
lkcl writes "Two independent projects, Skulpt and Pyjamas, are working to bring Python to the web browser (and the JavaScript command-line) the hard way: as JavaScript. Skulpt already has a cool Python prompt demo on its homepage; Pyjamas has a gwtcanvas demo port and a GChart 2.6 demo port. Using the 64-bit version of Google v8 and PyV8, Pyjamas has just recently and successfully run its Python regression tests, converted to JavaScript, at the command-line. (Note: don't try any of the above SVG demos with FF2 or IE6; they will suck.)"
As a high school computer science teacher, I can see a practical application of this. Currently, I think Python is one of the best languages to learn basic programming concepts with, in that it is relatively straightforward, powerful, and there's not much "voodoo" to prevent students from diving right into programming. It's possible to do some really cool things in Python with not much code.
However, one of the problems is that it can be difficult to give students a way to show off their code. Since it's an interpreted language, they can't just give an .exe or a .app file to someone else to show it off - they need to say, "Oh, go and install Python, and these libraries, etc." Yes, there are solutions such as py2exe and py2app, but getting these set up can be quite a task in itself. By running Python inside JavaScript, you basically open up the whole web-connected world as a potential audience to these budding programmers. It's much easier to say, "Hey, check out this link!" than "Hey, download Python (but get the right version) and this graphics library, then download my .py file, and open up a command prompt and type python blahblah.py!"
I prefer a javascript assembler
Found something better: 6502 assembler!
I felt the same way until I watched Douglas Crockford's videos on javascript. If you hate javascript, you're doing it wrong. I now prefer it to the other languages being discussed here.
i know you're joking, but there really _is_ a Visual Studio "universal translator" plugin available - i've seen it demo'd, converting c++ to java, to B, to ruby, to c#. it all used CLR as the intermediary. i heard that activestate were commissioned to add python to the mix, but, weirdly, it wasn't included in the release of the translator i saw.
Because it IS easier to use and hardware is always getting cheaper.
On the server side, 10x to 30x slower means building entire buildings full of servers. Or more expensive hardware in the cell phone. Or using another language.
Python is actually a good general-purpose programming language, not just a "scripting language". The big problem is slow execution.
The basic problem with CPython is that, being a naive interpreter, it has to check for the hard cases every time. "n = n + 1" ought to be a few machine instructions, maybe only one. But Python has to check for n being a float, n being a string, n being an object, etc., every time. Shed Skin, with a type inference systems, does analysis at compile time and determines that n is always an integer, then generates code for integer arithmetic only.
There are all sorts of dynamic things one can do to a Python program while it's running. You can add a function to an object. You can replace existing functions. You can load new modules on the fly. But most of the time, for most of the objects, you don't do that. An efficient implementation needs to separate out the cases where something unusual might occur, and the far more common cases when the program is doing routine stuff that needs to go fast. The common cases can then be handled with much simpler, and faster, code.