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.

Third in a series (#1, #2) of questions occupying my mind at the beginning of 2014. Which may (or may not) inform what I’ll be working on.

3) How can we program on tablets?

I’m now a tablet user. I became a tablet owner at the end of 2012. For six months I played around with it, trying a few Android programming exercises. But I only really became a regular tablet user half-way through the year. Firstly when I put Mind Traffic Control into a responsive design. Secondly when I bought a couple of e-books. And I only really got committed when I did OWLdroid and coupled that with btsync.

So – somewhat late to the party, I admit – I’m now a tablet enthusiast.

And so my question is, how the hell do I program on this thing?

There’s a trivial answer to that question : get an external keyboard, an appropriate editor / IDE and treat it like a normal computer with a small screen. I can do that. I’ve worked a lot on netbooks and small screens don’t freak me out. But that’s not really what I mean.

Because tablets aren’t meant to have keyboards. And a computer without a keyboard challenges one of my deepest held programming beliefs : the superiority of plain text.

Plain-text is so flexible, so expressive, so powerful, so convenient to work with, that I’ve always been highly sceptical of those who want to do away with it. But on a keyboardless computer, it’s a different matter. Plain text isn’t at all convenient without a keyboard.

Especially the text of programming languages which makes rich use of another dozen or so punctuation symbols beyond the alphabet and numerals. And where manipulation relies on cursor-keys, shift and control, deletes (both forward and backspace), page up and down, tab-complete etc.

And yet tablets are becoming ubiquitous. Increasingly they’re the target of our programming, and the tool we have with us. So how are we going to program in this new environment? With multi-touch or stylus but no keyboard?

I have yet to see anything even vaguely plausible as the revolution in programming “language” we’re going to need for this.

I don’t think it’s the “Scratch”-like or “App Inventor”-like “stick the blocks together” languages. The problem of programming on tablets shouldn’t be conflated with the problem of teaching novices to program. (Which is what most visual programming environments seem to be about.)

One issue with that kind of system (and other “flow-charts”) is that blocks need to be big enough to be easily and unambiguously manipulated with fat fingers. But to be decently usable, a programming system should be able to have a reasonable density of information on the screen, otherwise you’ll spend all your time scrolling and forgetting what you’ve seen. How do you resolve that tension?

Perhaps “data-flow” programming of the Max/MSP, PD, Quartz kind. Piping diagrams. Process Modelling packages have something to teach us about orchestrating in the large. But they are shockingly clumsy for certain fine-grained activities that are expressed easily in text. (Eg. how the hell can you talk about tree-shaped data or recursive algorithms using this kind of piping model?)

So I don’t have any information about who is doing interesting work in this area. (Aside : while writing this post, I thought I’d consult the collective wisdom on StackExchange. Needless to say, my question was immediately shot down as too vague.) But I’m now very curious about it.

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