Hacker Remix

Young Persons Guide to BCPL Programming on the Raspberry Pi [pdf]

62 points by scrlk 1 week ago | 28 comments

louthy 6 days ago

Page 29 is the first code. You need to work through 'War and Peace' of text before you get there. This is not good for a "young person". They need to get there quicker IMHO.

I always say that the reason I got into programming (at the age of 10) was because of the BBC Micro User Guide [1].

* Page 5: first code written (and importantly, code that has a visual component)

* Page 6: Drawing lines

* Page 7: Playing sounds

etc.

I realised very quickly that I was able to make a game. And that was it, I was hooked for life.

The Raspberry Pi took its inspiration from the BBC Micro (Model B). It's a shame that there wasn't more of a push to make it as easy as the original Model B to get going and start programming.

(Of course I realise that it's running Linux where nothing is simple, but yeah, I'm not sure it necessarily helps kickstart the next generation in the way the original BBC Micro did)

[1] https://archive.org/details/BBCUG/mode/2up?view=theater

tgv 6 days ago

I think the title is just a play on "A young person's guide to the orchestra" (by Britten). Nobody in their right mind would want to learn programming in BCPL, the predecessor of the predecessor of C.

louthy 6 days ago

> Nobody in their right mind would want to learn programming in BCPL

I agree, but that's not what the author thinks:

"When a new programming language is designed it is invariably strongly influenced by languages that preceded it. One thread of related languages is: Algol -> CPL -> BCPL -> B -> C -> C++ -> Java, indicating that BCPL is just a small link in the chain from the development of Algol in the late 1950s to Java in the 1980s. BCPL is particularly easy to learn and is thus a good choice as a first programming language."

Emphasis mine.

Also,

"This document is intended to help people with no computing experience to learn to write, compile and run BCPL programs on the Raspberry Pi in as little as one or two days, even if they are as young as 10 years old."

So, unless I'm missing something, this document is intended to teach programming first concepts with BCPL. And it seems like it's aimed at young people, regardless of the play on words (which I didn't know, thanks!).

lordmauve 6 days ago

> > Nobody in their right mind would want to learn programming in BCPL

> I agree, but that's not what the author thinks:

The author of this document is Martin Richards, the creator of BCPL. Of course he thinks you would want to learn it.

082349872349872 6 days ago

We've all been a young person[0], so it's easy to criticise from that angle.

However, I'd like to think the readership of HN are hacker enough to like to think that, given a desert island (with minor deps like sand and the Friday hardware fab!) and a few spare years, they'd be capable of Robinson Crusoe'ing up a personal development environment.

From that point of view, I find[1] this effort admirable: it's several hundred pages, by Martin Richards, about the port of the BCPL toolchain (language, compiler, bytecode interpreter, libraries, debugger, etc. all by Martin Richards?) to a new system (was it a new arch as well?)... by Martin Richards.

How many among us get a machine with new graphics, decide to write a flight simulator, and then —only as a minor[2] implementation detail mind you— plumb float support through our entire language ecosystem? Who needs a shaved yak when you're pursuing the buttery-smooth shaded yak?

[0] or maybe we even still are: https://news.ycombinator.com/item?id=42682353

"when I was your age all we had were 1's and 0's, and sometimes not even 0's, so we'd stay up all night xor'ing 1's to have enough for the next day..."

[1] when I did this sort of thing to pay the bills, I had someone else doing the tech writing and someone else providing toolchain and debugger sources, and it was still not a trivial lift.

[2] compare Wirth FPGA'ing up an entire homebrewed arch just so he could have a personal workstation using his favourite mouse.

tgv 6 days ago

You're right. I'm somewhat stumped.

anonzzzies 6 days ago

Before I even had a computer (begin 80s), my grandparents used to always bring me to a warehouse where they sold inventory from burnt down shops. Usually I would by soccer fan shirts (Ajax in my case at the time) and stuff, but this time, it was a specialist bookshop and I picked up a few computer books and magazines. This was so early in the computer era that I had never seen a computer magazine or book; I knew what computers were from the 2600 which my cousin had to play games on, but outside that I knew not very much. I read these things from cover to cover many (100 times possibly) times and always remember that when we did get our first computer, I opened my favorite one; it had the ISBN/author/publisher page and then page 1 was:

Turn the computer on and type

10 PRINT "My first homecomputer program"<enter>

RUN<enter>

And the book continued like that. I really cannot remember at all what the book was called or for which homecomputer it was; I do remember that after a bunch of pages, the programs stopped working on my system with a syntax error. I think it maybe was a ZX Spectrum or so book, but it hardly can be as I think it was too early for that. It was the fastest way to get into it and got me deep into programming because it went so easy that I kept finding more and more.

Tor3 6 days ago

Chapter 4.1 (installation of BCPL, before you can start coding) is indeed somewhat(!) more complicated than how it was for the BBC microcomputer (or any other back in the day) - just power it on, enter

  10 PRINT "HOW ARE YOU"
  RUN

guenthert 6 days ago

Nice introduction text with detailed description to set-up a R.Pi and interesting examples (AES, calculating Euler's number, Rubik's cube etc.). Shame it uses an utterly obsolete language of which most interesting feature (byte code interpreter making porting the compiler to new architectures comparatively easy) was important in the seventies with its plethora of architectures (many short-lives), but hardly today.

Rochus 7 days ago

Wow, this is an amazing book, nearly 800 pages; counless examples of BCPL applications, by the author of the BCPL language.

b800h 6 days ago

I'm going to test out the assertion that children as young as 10 can use the guide, by asking my 11-year-old to use it. I don't believe it; it assumes way too much knowledge of computer terminology. We'll see.

BCPL also looks dry as hell, I'm not convinced it's a great first language.