System programming in D (Was: The God Language)

[Walter Bright]

On 12/30/2011 6:59 PM, Timon Gehr wrote:
> On 12/31/2011 03:16 AM, Andrei Alexandrescu wrote:
>> On 12/30/11 6:25 PM, Timon Gehr wrote:
>>> I'd be happy to extend the system, but currently I don't see it fall
>>> short any of the three requirements. Can you help me out?
>>
>> I think it would be great to reproduce the expansion semantics of ddoc.
>>
>> Andrei
>
> So basically, just breaking infinite recursion on recursive identical
> instantiations?
>
> In what way does such a feature improve the expressiveness of the macro system?

Because inevitably someone will write:

#define FOO   a + FOO

and expect it to work (the correct expansion would be "a + FOO", not a stack 
overflow). The C preprocessor works this way, as do makefile macros, as Ddoc does.