I realize that trying to teach how to write, for example, a C compiler would bog things down because of all of the real-life complexity needed to handle things like different data type lengths, but this was where I gave up because I could see that I was being led down a “this is easy” path that wasn’t going to actually serve me. If I’m going to spend a bunch of time writing a hardware simulator, where’s the fun if it won’t work for any practical circuit, and similar argument about the limited high-level language. Together, these are just too “hand-wavy” for my taste. Posted in classic hacks, computer hacks, Software Hacks Tagged binary, compiler, hello world, s-expression Post navigationĪn excellent course/book, with just a couple of flaws: 1) it starts you off by teaching you about gates and having you write a simulator for logic to test your exercises, but that only works up to the point where you need to use flip-flops, at which point they have you switch to their simulator rather than losing students at the stage of trying to get flip-flop timing to work in simulation, and 2) the high-level language they use to teach how to build a compiler is not a language anybody would actually try to use in real life. Operators would work with pencil and paper to convert programs into machine code, and you can get a taste of that with a project that re-creates what it was like to program a computer using just a few buttons as inputs. Working at such a low level can be rewarding, but back in the day the first computers actually relied on humans to be compilers. ssize_t write(int fd, const void *buf, size_t count) Here’s what the code for “Hello world!” looks like before being fed into the compiler: It’s tiny, the only data types are integers and pointers, and all it can do is make Linux syscalls - but it’s sufficient to make a program with. The (very tiny) compiler is on GitHub as The Pretty Laughable Programming Language. The GitHub repository linked below has everything one needs, but also wrote a book, From Source Code to Machine Code, which he offers for sale to anyone who wants to step through the nitty-gritty. ’ compiler - created from scratch - makes native 圆4 Linux ELF binary executables with no dependencies, an experience found both educational and enjoyable. Here’s what happens with a compiler: human-written code gets compiled into low-level machine code, creating a natively-executable result for a particular processor.

demonstrates by making a tiny compiler for an extremely simple programming language, and showing off a hello world.

Believe it or not, building a tiny compiler from scratch can be as fun as it is accessible.

Online lex and yacc compiler