Why not allow empty code blocks?

[Chris Angelico]

On Wed, Aug 3, 2016 at 11:23 PM, BartC <bc at freeuk.com> wrote:
> On 03/08/2016 09:58, Steven D'Aprano wrote:
>
>> Python is sometimes described as a Lisp with more sensible syntax, so its
>> not
>> surprising that it is relatively simple to translate Python to Lisp and
>> visa
>> versa.
>
>
> Translating Python would be easier if everything was implemented as Python.
> But sometimes you try to find a .py import module and it doesn't seem to
> exist anywhere. (sys.py for example).
>
> I would like to see how such references are translated to Lisp.

Ultimately, you _cannot_ implement everything in Python, unless you
create some sort of crazy fudge like having function pointers with
real language support, in which case you're writing C code. Some
modules have to be implemented in the host language (C for CPython,
Java for Jython, etc), in order to provide lower-level functionality.
You probably *could* implement the whole math module in pure Python,
but you don't want to; and cryptography, likewise, you theoretically
could implement in pure Python, and you'd get the same return value,
but you risk opening yourself up to timing-based attacks.

How, from Lisp, would you call on OpenSSL or another lower-level
library? Or do you have to reimplement everything? What about simple
things like opening files, how do you do that without native code?

ChrisA