On Sep 1, 5:31 am, Steven D'Aprano
<ste...@remove.this.cybersource.com.au> wrote:
>
> You can pass in a global and local namespaces to exec as arguments:
>
> >>> x = 4
> >>> ns = {'x': 4}
> >>> exec "x += 1" in ns
> >>> x
> 4
> >>> ns['x']
>
> 5
>
> See the docs for details.Thanks! This is very useful! > You can copy the parts of the current scope into the namespace you pass > to exec, then later copy the revised values out again. > > But are you sure you really want to take this approach? exec is up to ten > times slower than just executing the code directly. And if the string is > coming from an untrusted source, it is a *huge* security risk. I don't know if I should use exec. I don't really mind that it's slow (btw., why is it so?). But I don't quite understand why is it security risk. How is it different to run: exec 'format(your_hdd)' than: /bin/python format.py ? > As far as I know, you can't kill threads, you can only ask them to kill > themselves. Also, I'm not sure if I follow. What does this mean? If a thread runs: while True: pass it is not possible to kill it from another thread? (Bacause it doesn't check whether some other thread asks to stop it..?) > Something like this? Well, something more like: data = [1, 2, 3] map(lambda x: x * 2, data) display_data_in_editor_viewport(data) #this renders into part of main editor window (may take some time) > If so, I think you are making this much too complicated for such a simple > use-case. Just publish an API which the script can use, and have the main > text editor application specify a "script" namespace containing only that > API. That could be a module: > > >>> import math # pretend this is your API shared module > >>> exec "myvalue = 42" in math.__dict__ > >>> math.myvalue > > 42 > > Then execute the text using exec, but don't bother about putting it into > a thread or subprocess. That just makes it harder to implement, and you > have to worry about concurrency issues. Ok, I could try exec, thanks for the explanation. But what about those security concerns you mentioned above? Thanks a lot, very informative! -- http://mail.python.org/mailman/listinfo/python-list
