Lee Simpson wrote:
Damn. I've just implemented the whole algorithm using your suggested approach, and I've come across a problem. I don't have a simple way to describe my dilemma, so a complex way will ave to do :-/
The best way is to post source code.
First of, I'll describe the way I have implemented your suggestion. First off, I utilize an expression of the form ((s1 = expr) >> keep(nil[action(_,...)])) for each significant component of the expression. <snip>
Stop right there. Are you really using nil[action(_,...)] ? In this context, xpressive will replace _ with the submatch corresponding to the subexpression to which the semantic action is attached. In this case, the action is attached to nil, which always matches 0 characters. So your action will always be passed an empty submatch. I bet that's not what you want. Did you intend nil[action(s1,...)] perhaps? -- Eric Niebler BoostPro Computing http://www.boostpro.com