Creating a reliable sandboxed Python environment

[BartC]

On 29/05/2015 23:49, Chris Angelico wrote:
> On Sat, May 30, 2015 at 4:33 AM, Paul Rubin <no.email at nospam.invalid> wrote:
>> Chris Angelico <rosuav at gmail.com> writes:
>>> Looks to me as if Lua doesn't have integers at all
>>
>> They fixed that in Lua 5.3:
>>
>>    http://www.lua.org/manual/5.3/readme.html#changes
>
> That's 64-bit integers, not arbitrary-precision, but that's something
> at least. You do still need to worry about what happens when your
> numbers get too big; in Python, you simply don't. So it's still not
> quite there in terms of functionality.

But then the vast majority of integer operations won't require arbitrary 
precision. (Or maybe Python programmers routinely use big integers all 
over the place simply because they can.)

>>> Likewise, eight-bit strings, not Unicode.
>>
>> Also fixed in 5.3 (basic utf-8 support added, per above).

> Do you see what I mean about functionality being sacrificed for
> security? There is no way that this could be called fully functional
> by comparison with Python.

Python seems to have sacrificed some performance. When I questioned why 
3.x was slower than 2.x, merging int and long int (as I understood it) 
was one of the reasons put forward.

(Simplicity seems to work for Lua. The entire distribution (for LuaJIT 
2.0), seems to be about 2MB, including C sources, and the JIT 
interpreter is about 220KB. LuaJIT was also one of the fastest dynamic 
languages I've tried. But you're right that the language is rather sparse.)

-- 
Bartc