- bool match = false;
- string::size_type equals = cond.find('=');
- if(equals!=string::npos)
- {
- if(equals==0)
- throw invalid_argument("SourcePackage::Loader::if_feature");
- bool negate = cond[equals-1]=='!';
- string name = cond.substr(0, equals-negate);
- string value = obj.config.get_option("with_"+name).value;
- match = (value==cond.substr(equals+1))!=negate;
- value = cond.substr(equals+1);
- }
- else
- {
- bool negate = (cond[0]=='!');
- string name = cond.substr(negate);
- string value = obj.config.get_option("with_"+name).value;
- match = lexical_cast<bool>(value)!=negate;
- }
+ BooleanEvaluator eval(sigc::mem_fun(&obj, &SourcePackage::match_feature));
+ bool match = eval.evaluate(cond);