On 1/9/2011 9:20 PM, Joel de Guzman wrote:
On 1/10/2011 9:58 AM, Eric Niebler wrote:
I don't know about the "fully typed attributed" part, but type-erasure has nothing to do with it. Xpressive regexes are also type-erased. Only regex algorithms begin the pattern match. That entry point is what sets up the action context, and only the end state of the outermost regex causes the chain of actions to execute. Trust me, it works.
Of course I trust you! :-) But what works for xpressive might not work with Spirit.
What is the signature of your lazy actions stored in the queue?
Ah, that's a perceptive question that cuts to the quick. That function accepts only iterators into the matched string and returns void. No attributes.
How do you make it accept and return arbitrary types (attributes)? Inherited attributes may make use of continuation passing style but synthesized attributes can't. That's what I meant. of course attributes do not matter in xpressive.
Different design, different trade-offs. I still don't know whether Spirit's attributes preclude lazy action invocation, though. I tend to agree with Joel that performance comparisons between xpressive and Spirit and not that interesting. -- Eric Niebler BoostPro Computing http://www.boostpro.com