Vincent Finn wrote:

I am thinking of using spirit for C++ style expressions and am wondering if it is the way to go

What I have will be something like ( (A != 192) AND ( (V > 0) AND (V < "89") ) )

What I need is to be able to parse this replace the AND, > etc... with operations, replace string numbers with real numbers and then apply the operation to a large number of A and V.

I would have thought this would be quite a common usage but I haven't seem any samples doing it of partictuar importance is the delayed evaluation

Anyone have an example of this?

You may want to have a look at Wave (a Standard conformant C++ preprocessor, documentation: http://spirit.sourceforge.net/index.php?doc=docs/wave_v0_9/index.html, download: http://spirit.sourceforge.net/index.php?doc=download/Wave_0_9.html), which is build with the help of the Boost.Spirit library and which contains a full fledged C++ expression evaluator (for the #if/#elif directives). Regards Hartmut