What is the best way to avoid the: 'class' type redefinition errors? This comes from anytime I include a header for a file that has already been included somewhere else. First of all, why is this a problem, and second, what a quick and easy way to fix this.
thanks
-from looking at previous post it looks like my answer has something to do with either "using namespace std" or "#ifndef"
chris
for example, a main.h file
Code:#ifndef _MAIN_H #define _MAIN_H //...............code here #endif
You can't declare or define things twice.First of all, why is this a problem
Use inclusion guards, as EvBladeRunnervE has shown.and second, what a quick and easy way to fix this.
To add to ' EvBladeRunnervE' post...
Code:#ifndef _MAIN_H #define _MAIN_H #ifndef _STDIO_H #include <stdio.h> #endif #ifndef _STDLIB_H #include <stdlib.h> #endif //...............code here #endif // !_MAIN_H
Code:#include <cmath> #include <complex> bool euler_flip(bool value) { return std::pow ( std::complex<float>(std::exp(1.0)), std::complex<float>(0, 1) * std::complex<float>(std::atan(1.0) *(1 << (value + 2))) ).real() < 0; }
