Re: [boost] [proprocessor] PP challenge!

From: Tobias Schwinger (tschwinger_at_[hidden])
Date: 2006-11-06 17:27:06

Daniel Wallin wrote:
> Tobias Schwinger wrote:
> 
>>Daniel Wallin wrote:
>>
>>>Eric Niebler wrote:
>>>
>>>
>>>>I'd still be curious what a PP solution looks like, though. The problem 
>>>>stumped me for quite some time.
>>>
>>>I'll bite. It's a bit of a hack, but it works. :) It basically
>>>accumulates the closing >'s as it goes, and expands them after the last
>>>item. It keeps a looping counter that keeps track of when to split into
>>>another mpl::and_<>.
>>>
>>
>>Here is an alternative implementation with a similar approach, using
>>a sequence to "escape" the commas and SEQ_ENUM for "unescaping".
> 
> 
> Yes, FWIW my rationale for doing it the way I did was that I wanted to
> allow the predicates to have embedded commas. Also, it's *a lot* faster,

I figured it would be superior in terms of performance - the massive 
expansion certainly takes its toll. 

My objective was to keep it simple and easy to follow.

> and this is a contest, right? ;)

Dunno... But if it is Dave started the next lap - go for the play-off :).

Regards,

Tobias