Using a pump wave

Question

I’m trying to raise my head above the rising wave, and still I’m not very lucky.

I tried a sample code from the site. It is below:

#include <iostream> #include <iomanip> #include <fstream> #include <string> #include <vector> /////////////////////////////////////////////////////////////////////////////// // Include Wave itself #include <boost/wave.hpp> /////////////////////////////////////////////////////////////////////////////// // Include the lexer stuff #include <boost/wave/cpplexer/cpp_lex_token.hpp> // token class #include <boost/wave/cpplexer/cpp_lex_iterator.hpp> // lexer class int main () { // The following preprocesses a given input file. // Open the file and read it into a string variable std::ifstream instream("lex_infile"); std::string input( std::istreambuf_iterator<char>(instream.rdbuf()), std::istreambuf_iterator<char>()); // The template boost::wave::cpplexer::lex_token<> is the // token type to be used by the Wave library. // This token type is one of the central types throughout // the library, because it is a template parameter to some // of the public classes and templates and it is returned // from the iterators. // The template boost::wave::cpplexer::lex_iterator<> is // the lexer iterator to use as the token source for the // preprocessing engine. In this case this is parametrized // with the token type. typedef boost::wave::cpplexer::lex_iterator< boost::wave::cpplexer::lex_token<> > lex_iterator_type; typedef boost::wave::context< std::string::iterator, lex_iterator_type> context_type; context_type ctx(input.begin(), input.end(), "lex_infile"); // At this point you may want to set the parameters of the // preprocessing as include paths and/or predefined macros. //ctx.add_include_path("..."); //ctx.add_macro_definition(...); // Get the preprocessor iterators and use them to generate // the token sequence. context_type::iterator_type first = ctx.begin(); context_type::iterator_type last = ctx.end(); std::cout << "HERE" << std::endl; // The input stream is preprocessed for you during iteration // over [first, last) while (first != last) { std::cout << (*first).get_value() << std::endl; ++first; } } 

It compiles fine, but when I enter the file into it, I get the following error:

ending the call after calling the instance "boost :: exception_detail :: clone_impl>"
what (): boost :: wave :: preprocess_exception
Canceled

The code I'm trying to "preprocess" is in a file called lex_infile with the following contents:

 #include <oglre> #include <light> #include <material> in vec3 in_Position; in vec2 in_Texture; in vec3 in_Normal; out vec2 textureCoord; out vec4 pass_Color; void main() { gl_Position = pvmMatrix * vec4(in_Position, 1.0); textureCoord = in_Texture; vec3 normalDirection = normalize(normalMatrix * in_Normal); vec3 lightDirection = normalize(vec3(lightSources[0].direction)); vec3 diffuseReflection = vec3(lightSources[0].diffuse) * vec3(mymaterial.diffuse) * max(0.0, dot(normalDirection, lightDirection)); /* float bug = 0.0; bvec3 result = equal( diffuseReflection, vec3(0.0, 0.0, 0.0) ); if(result[0]) bug = 1.0; diffuseReflection.x += bug; */ pass_Color = vec4(diffuseReflection, 1.0); } 

I guess I need to determine include locations .... how could I do this?

Sorry if this is simple stuff, I'm a little lost.

Answer 1

Figured it out.

I need to extend the class public wave::context_policies::default_preprocessing_hooks and then override the found_unknown_directive method.

Once this was done, I needed to pass my new transition interception class to typedef boost::wave::context as a template parameter.

It looks like this:

 typedef boost::wave::context< std::string::iterator, lex_iterator_type, load_file_to_string, custom_directives_hooks > context_type; 

and

 class custom_directives_hooks : public wave::context_policies::default_preprocessing_hooks { public: template <typename ContextT, typename ContainerT> bool found_unknown_directive(ContextT const& ctx, ContainerT const& line, ContainerT& pending) { typedef typename ContainerT::const_iterator iterator_type; iterator_type it = line.begin(); wave::token_id id = wave::util::impl::skip_whitespace(it, line.end()); if (id != wave::T_IDENTIFIER) return false; // nothing we could do if (it->get_value() == "version" || it->get_value() == "extension") { // Handle #version and #extension directives std::copy(line.begin(), line.end(), std::back_inserter(pending)); return true; } if (it->get_value() == "type") { // Handle type directive return true; } // Unknown directive return false; } }; 

Hope anyone else can solve this problem.