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C4 – C in 4 functions

(github.com)
517 points petercooper | 2 comments | 04 Nov 14 20:19 UTC | HN request time: 0.506s | source
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jdp ◴[05 Nov 14 04:15 UTC] No.8560488[source]▶
This is really similar to Marc Feeley's tinyc.c[0], which implements a C subset parser, code generator, and virtual machine in about ~300 lines of C.

[0]: http://www.iro.umontreal.ca/~felipe/IFT2030-Automne2002/Comp...

replies(1): >>8560552 #
abecedarius ◴[05 Nov 14 04:47 UTC] No.8560552[source]▶
That's a nice one. The big difference is that it doesn't compile itself -- not that there's anything magical about that, but it's a kind of threshold of seriousness.
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1. userbinator ◴[05 Nov 14 09:06 UTC] No.8561017[source]▶
One of the things I've wondered about is how small one could make an ISO C89-compliant compiler (that would be able to compile itself), and all these tiny compiler projects have inspired me to revisit that thought now... I've written pieces of compilers like expression parsers and tokenisers, and even then I felt like it wouldn't be so hard (if I had the time) to write a full compiler.

These are all great for dispelling the notion that all compilers somehow necessarily have to be greatly complex and impenetrable to anyone but highly-trained professionals and theoreticians. (Look at the Dragon Book, for example.)

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2. abecedarius ◴[05 Nov 14 19:15 UTC] No.8563634[source]▶
You might enjoy http://canonical.org/~kragen/sw/urscheme/ -- it's by someone who'd just written his first compiler, with links to other sources he found inspiring (one of them mine).

C89 I think has too much complexity for the amount of power it offers. lcc is a nice example: Norman Ramsey said he asked one of the authors what he learned in writing it, and got an answer like "Not to write a compiler in C." But anyway the book about it https://sites.google.com/site/lccretargetablecompiler/ is very good. http://www.cs.princeton.edu/~appel/modern/ is my favorite general text.