Comment by dragonwriter | Hacker News Reader

Comment by dragonwriter | Hacker News Reader

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> Because Lisp is homoiconic, you don't code in (what I personally believe to be) reasonable syntax, you code in abstract syntax trees.

There's no reason a regular macro couldn't implement a basically C-like syntax (though it would have Lisp, not C, tokenization rules, to the extent that those are different) on what is passed as its argument. The actual call to the macro would have typical Lisp syntax, but what the macro consumes would be interpreted with whatever syntax was implemented by the macro.

(And, a reader macro could implement more deeply C-like syntax.)

Well, for regular macros, only if your C syntax was in a string. Otherwise, lisp would try to tokenize it, and choke. Heck, if your lisp of choice offers an eqivalent of TCL's uplevel, you wouldn't even need a macro, just a function.

> Well, for regular macros, only if your C syntax was in a string. Otherwise, lisp would try to tokenize it, and choke.

Which is why I said normal (rather than reader) macros could do a "basically C-like syntax" but with Lisp tokenization rules.

What would that look like?

  ((:include "stdio.h")
  
  (const char * message = "Like this.\n")
  
  (int main ((int argc) (char * * argv))
    (printf message)
    (return 0)))

Ah.

I've never seen something like this before--do you know of any examples of this kind of macro usage?

This article provides a simpler (but conceptually similar, where it comes to implementing syntax different than standard Lisp S-expression syntax) example of using reader macros to implement JSON literals in Lisp.

https://gist.github.com/chaitanyagupta/9324402

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