Another Quora answer : Phil Jones’s answer to Why is C++ considered a bad language?

This is one of those rare occasions I disagree with Simon Kinahan; although his answer sets the scene for this one.

[Simon says that C++ isn’t a bad language. It’s the right choice if you need low-level memory control and the ability to build powerful higher-level abstractions.]

C++ is a bad language because it’s built on a flawed philosophy : which is that you should add power to a language by kludging it in “horizontally” in the form of libraries rather than “vertically” by building new Domain Specific Languages to express it.

Stroustrup is very explicit about this, rhetorically asking “why go to other languages for new features when you can add them as libraries in C++?”

Well, the answer is, adding new higher level conceptual thinking in the form of a library doesn’t really hide the old thinking from you. Or allow you to abandon it.

C++’s abstractions leak, more or less on purpose. Because you can never escape the underlying low-level thinking when you’re just using this stuff via libraries. You are stuck with the syntax and mindset of the low-level, even as you add more and more frameworks on top.

Yes, you can explicitly add garbage collection to a C++ program. But you can’t relax and stop thinking about memory management. It can’t disappear completely beneath the horizon of things you need to be aware of the way it does in Java.

Yes, you can have higher-level strings, that can abstract Unicode-ness etc. via a library. But you can never be sure that you won’t confront strings that are simple byte-arrays coming from another part of your large system.

Etc.

C++’s ability to build high-level abstractions uncomfortably falls between two stools.

It encourage you to think you can and should be building large applications full of application logic. But doesn’t give you the real abstracting power to focus only at that application level.

This explains the otherwise mysterious paradox that C is a good language, so how could something that is “C plus more stuff” possibly be a bad one? Well, it’s exactly the “more plussing” that’s the problem.

With C, you KNOW you should only use it to build relatively small things. It doesn’t pretend to offer you mechanisms to build big things. And so you turn to the obvious tools for scaling up : lex and yacc to build small scripting languages, the Unix pipe to orchestrate multiple small tools . C++ gives you just enough rope to hang yourself. Just enough powerful abstraction building capacity in the language itself that you (or that guy who used to work in your company 15 years ago ) thought it might be possible to reinvent half of Common Lisp’s data-manipulation capability and half an operating systems’ worth of concurrent process management inside your sprawling monolithic application.

I don’t see why it shouldn’t be possible to combine low-level memory management and efficiency with high level abstraction building. But proper abstraction building requires something more like macros or similar capabilities to make a level of expression which really transcends the low level. That’s exactly what C++ lacks.

Very interesting. Recently my “ProgrammingInWiki” page on WardsWiki seems to have come back to life. Along with a companion WikiIDE.

A WikiDE is, of course, something I’ve been working on in the background for some time. But I’m far from having anything to show yet. So if these guys get there first, good luck to them.

I just want to be able to start working this way.

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And I thought I was ambitious, trying to write a programming language!

My friend Oli has decided to reinvent programming as we know it. Details are still trickling out via his web-site : Semantic Programming. And I’m in frenzied skype conversation with him, trying to figure out what it’s all about.

In outline, it starts from some intuitions behind the Semantic Web : that there should be a massively parallel, distributed graph-shaped database of facts (relational assertions) represented on different machines across the world. But it then layers programming on top of that. Instead of a passive data-structure crawled by scutters, SemProg agents (roughly, the servers which manage different data-nodes) are active. There is message passing between the facts themselves, and agents may have hardwired interpretation to act on some facts (what Oli is calling “axiomatic” understanding), or a “deductive” understanding (I guess rather like Prolog inference), and even a “behavioural” understanding via (I guess again) learning from observing other agents.

I’ll keep following this here on Smart Disorganized. Very interesting if it works out.

Would GeekWeaver support Semantic Programming? It seems like Oli is thinking of multiple editors for different types of information, all of which compile down to the same underlying graph-structured format so that the data can be combined. (Rather like Language Oriented Programming.) It seems quite possible that GeekWeaver could output something like his graph-format. I’ll certainly be experimenting.

I’m also trying to persuade Oli to look at Erlang as a potential implementation language for the distributed virtual machine. I’m increasingly impressed by Erlang. Finding it very powerful and concise.

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