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PyPy.js: Python in the web browser

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Re: PyPy.js: Python in the web browser

#51

Post by chillydawg »

Klathmon wrote: post #48
Alupis wrote: post #44

Didn't we decide a long while back that fully featured programming languages were dangerous in the browser, especially if they could do disk I/O? Even if sandboxed? A la Java Applets and Adobe Flash? import os for subdir, dirs, files in os.walk('./'): for file in files: print file os.remove(file) Perhaps the environment is "fake", and these files don't really exist, even in some sandbox... otherwise, seems like this…

I don't know about PyPy.js specifically, but most systems like this provide a virtual filesystem that maps back to things like indexedDB and localstorage which are browser APIs. There is no way that pypy.js is able to access local files on your machine outside of the browser sandbox.

I bet there's a few cheeky hackers around the world who may disagree with that statement. Always assume it's broken.

Re: PyPy.js: Python in the web browser

#52

Post by lucb1e »

The speed is surprisingly reasonable. Testing with a simple loop, I get about 1.3-1.4 million loops per second in python3, 2 million loops per second in python2, 14.5 million loops in pypy, and 0.61 million loops in the browser.

My code basically calls int(time.time()) until its value changes, doing i+=1 for every time it did not change (n=10 for every platform (python2/3/pypy/browser)). My browser is Firefox 61, full code here: https://hastebin.com/turenofise.py

Re: PyPy.js: Python in the web browser

#53

Post by aswanson »

typon wrote: post #47
rkeene2 wrote: post #35

Earlier quoted context omitted.

I've been thinking about building this for Tcl. Tcl has been available in the browser in various forms for decades, but one thing that makes Tcl uniquely suited to a web application style development is its threading model. In Tcl, you access a thread by sending messages to it, in which a Tcl interpreter inside its event loop processes. My plan was to have a client-side Tcl program in the browser that automatically i…

But then you have to code in... Tcl...

Exactly. Ugh.

Re: PyPy.js: Python in the web browser

#57

Post by rkeene2 »

typon wrote: post #47
rkeene2 wrote: post #35

Earlier quoted context omitted.

I've been thinking about building this for Tcl. Tcl has been available in the browser in various forms for decades, but one thing that makes Tcl uniquely suited to a web application style development is its threading model. In Tcl, you access a thread by sending messages to it, in which a Tcl interpreter inside its event loop processes. My plan was to have a client-side Tcl program in the browser that automatically i…

But then you have to code in... Tcl...

Then you GET to code in Tcl !

Re: PyPy.js: Python in the web browser

#58

Post by lucb1e »

Alupis wrote: post #44

Didn't we decide a long while back that fully featured programming languages were dangerous in the browser, especially if they could do disk I/O? Even if sandboxed? A la Java Applets and Adobe Flash? import os for subdir, dirs, files in os.walk('./'): for file in files: print file os.remove(file) Perhaps the environment is "fake", and these files don't really exist, even in some sandbox... otherwise, seems like this…

This is Javascript, not real Python. If you're so afraid that this is dangerous, why do you post malicious code? And if you're so clever to post that code, why don't you try similar code to see if it really has access to your files?

    import os
    os.listdir('/')
The answer, by the way, is no.
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