After spending the past year or so developing large Python applications, I’ve returned back to the C++ fold for my day to day work. For a long time, I developed primarily in C++, enough that the compiler became my tool of choice for simple automation tasks over the more logical scripting platforms. Large applications in a scripting language? Lunacy. And now, returning back to C++ feels painful. Time to spend some time trying to figure out why. I’m hoping to perhaps uncover some improved style for my C++ implementations with this introspection.
Build Systems All Suck
Being interpreted, Python doesn’t require any build systems. Drop in a .py file and it’s off to the races. Drop __init__ into a directory for a package. Simple. Python distribution utilities generally equate to a list of required dependencies readily served up from a pypi repository. In C++ land, we’ve got CMake, Waf, Autotools, Makefile, MS Build, and any number of other alternatives. Pick any one – and quickly you’ll be staring in the monitor wishing you’d chosen differently when some IDE, library, or maintenance task gets in the way. Unfortunately, I’m not sure there’s anything to be done here outside of inventing yet another new standard.
Dynamic Typing vs Generics, Virtual Methods, and Templates
Dynamic Typing with static hinting / analysis just feels more natural than the world of static types no real introspection. Concepts may help bridge the gap here – as, I find myself mostly treating all my Python functions as accepting concept inputs. Further, since all the classes are dynamically bound, there’s no need for a central module to be aware of a plugin module class type or define an interface for it. Perhaps a solution here would be a combination of CRTP and C++20 concepts – or maybe helper methods? Some experimentation is needed. SFINAE substitutions may be able to aid with attribute looking using named class members.
Coroutines and Async
C++20 is hopefully going to help here – but I’ve yet to see a good example (and try out a compiler supporting), the new coroutines spec. Further, C++20 support here seems embryonic and tailored HIGHLY toward library authors. The more I’ve worked in Python, the more I find myself utilizing generators, and lately, async generators, and in some cases, full-on async coroutines. Database search operations, network operation – so much easier to utilize async with the ‘await’ keyword, versus traversing seas of callbacks.
File and Module Namespaces
This one has me pondering adopting a new scheme of defining per-file namespaces in C++ and utilizing using in top ‘module’ directories. More thought is needed – but, my initial thought here is there’s a certain niceness to each python module polluting only it’s own namespace. In C++, a single “using” statement can derail a whole include train traversal. Worse, you’ve got to worry about any third party throwing their crap in as well.
Missing REPL in the Debugger
In Data analysis, there’s no end to the power of a well populated workspace. The primary benefit I find in Matlab is simply the data visualization toolset and ability to have a workspace that your actively manipulating and saving small chunks of to use later. My Python development often sees one window left open with a REPL, in where I’m continuously trying new code segments and verifying operation.
List Comprehensions
This is right up there with generators and co-routines. The ability to build a list directly instead of appending to one – especially as that can be done internally with an iterator allowing filtering and mapping without large intermediary data structures. Will also need to check this out with C++20.
I’ll reserve some space to whine more later – but I think this covers at least the top level points from a language standpoint. I haven’t talked about the elephant in the room that is pypi and the current rather sad C++ ecosystem there. That said, with my current project, so much of the code was developed in house, that using an off the shelf framework like Qt and following up with entirely custom development would be roughly comparable.
Whatever your language of choice, diving into another land and trying to bring back some ideas with you is a powerful way to improve the skill set. Good hunting.