example for compile time function execution

[Daniel Keep]

Robert Fraser wrote:
> Walter Bright Wrote:
> 
>> I keep racking my brain trying to come up with a short, pithy example of 
>> CTFE that uses AAs or struct literals. It should be just a few lines, 
>> and make it clear why CTFE is a great thing. I want to use it in 
>> presentations.
>>
>> Any ideas?
> 
> How about one that, given a function pointer/delegate and the name of a Java package, wraps it for the JNI with the correct naming scheme and C calling convention.

I don't think you could do that with CTFE.  Unless I'm missing
something, CTFE can only generate values, not code or types.

Well, not unless you involve the mixin keyword, but there doesn't seem
to be anything you can do with that that couldn't be done with templates.

I think that, at this stage, CTFE doesn't really *have* one awesome
example you can point to and say "is it not nifty?"  The "problem" is
that CTFE seems to be a nicer way of generating source code strings and
other values at compile time.

Maybe you could show CTFE being used for pre-computing a table of sine
and cosine values, or show it being used to generate a source string as
compared to an equivalent template version.

That, or you could use that brainf*ck compiler someone wrote using CTFE.
 At least, I think it was CTFE...

	-- Daniel

-- 
int getRandomNumber()
{
    return 4; // chosen by fair dice roll.
              // guaranteed to be random.
}

http://xkcd.com/

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