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Comment by xscott | Hacker News Reader

I think the two of you are talking past each other. You're saying, "yes, you need a symbol table", and he's saying, "yes, but a symbol table isn't very hard to do".

Personally, I wonder how many of these things would go away if pointers were a suffix operator with a different character (maybe the @ sign), and if casts looked like function calls.

   A B@;   # B is a pointer to type A
   A(-B);  # A is either a function or a type for casting
           # Same AST regardless

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As for symbol tables being hard to do, notice that C does not allow forward references. Supporting forward references while relying on the symbol table to drive the parse winds up with unresolvable problems.

I'm not sure I understand your point. I don't think we're disagreeing about anything.

C needs forward declarations for some things, and it needs a symbol table to resolve some parts of the grammar. All I was saying was that I think you could resolve both of them with minor changes. (I see that D has a "cast" keyword, and that's obviously one way to do it.)

> A B@; # B is a pointer to type A

IIRC that's how Pascal did it, using a caret ^ for denoting a pointer.

Yeah, now only if Pascal had used curly braces, all could be right in the world :-)

Arh.... But then it wouldn't be Pascal ><

Yes! As he said - all would be right with the world =)

It was more about AT&T monopoly I believe :)

I don't know about Pascal, but AT&T allowed anyone to write a C compiler without needing a license. (C++, too, I know because I asked AT&T's lawyers.)

Kind of.

A pointer to type A is:

     var B: ^A

The parser knows it is a declaration because of the var, and it knows ^A is the type, because of the colon. That it is a caret does not really matter here

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