RE: [Boost-Users] Spirit for C++ style if expressions

From: HartmutKaiser_at_[hidden]
Date: 2003-06-12 12:45:48

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