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Comment by simias | Hacker News Reader

Oddly enough I find that the #define macro soup detracts from the performance here. I was rather unimpressed at first because obfuscating C code by just #define'ing a bunch of code is a trivial and rather uninteresting way to write unreadable code. Of course you can make any arbitrary code look like a printf call with enough macros!

But it's actually a lot more clever than that.

I feel like this would be a lot more impressive if it was written in simple and clear C since then you'd see that there really isn't any tic-tac-toe logic being explicitly implemented the way you'd expect.

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If you are curious, this is what the resulting format string looks like after expanding all the macros:

https://gist.github.com/hugomg/73e91ebca7ced3c5c6f955e9e830b...

The reason he had to use macros is that the actual formatting string is huge and difficult to understand. In this case, macros really serve a useful purpose, instead of just obfuscating code.

Another reason is that this was intended as an IOCCC submission and IOCCC has a file size limit.

One time, I had to maintain C code That somebody had #define'd to look like FORTRAN. It was impressive.

I've had to deal with code like that, only poorly mimicking Lisp instead: `#define unless(_x) if (!(_x))` etc...

One of my favourite accidental features in Rust is that macros are so annoying and cryptic to write that people think twice before abusing them.

Wouldn't be surprised if that was intentional, actually. The idea of making syntax a little unwieldy for things that you should really think twice before using is not a new one.

I understand the temptation. I keep catching myself on writing `unless( ... )` in C++ every couple days, and I've considered adding a macro for it, but ultimately decided against it, as the rest of the team would not understand why I need it.

One time, I had to maintain FORTRAN code. Much of it was still in FORTRAN 66.

Much of the original Bourne shell was written in C that had been macro'd to look like Algol [1].

E.g.

    /usr/src/cmd/sh/mac.h:
    #define IF      if(
    #define THEN    ){
    #define ELSE    } else {
    #define ELIF    } else if (
    #define FI      ;}
    
    #define BEGIN   {
    #define END     }
    #define SWITCH  switch(
    #define IN      ){
    #define ENDSW   }
    #define FOR     for(
    #define WHILE   while(

[1] https://research.swtch.com/shmacro

Quite some time ago I saw a piece of C code (probably linked from here) in APL style, I have been trying to find it since, does anyone know what I mean?

Might have been this. The style is usually attributed to Arthur Whitney:

https://code.jsoftware.com/wiki/Essays/Incunabulum

"The determined Real Programmer™ can write FORTRAN in any language."

Real Programmers write machine code in any language, thank you very much. (Which TFA rather nearly is, actually, though it's a bit macro-assemblery for a proper example.)

http://www.catb.org/jargon/html/story-of-mel.html

The macros are a form of data compression. Otherwise the string would be absurdly huge

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