/** @file

* Examples of setting the invalid error input handler in C++14,

* overriding the default behaviour of immediately exiting.

*

* @author Tyson Jones

*/

#include "quest.h"

#include <iostream>

#include <stdexcept>

#include <stdlib.h>

void myErrorHandlerA(const char* errFunc, const char* errMsg) {

std::string func(errFunc);

std::string msg(errMsg);

std::cout

<< "an error?? in the '" << errFunc << "' function?? with message '" << msg << "'! "

<< "how queer!! ive never seen such a thing - i must throw an exception post-haste!!!"

<< std::endl

<< std::endl;

// exception forces control-flow out of QuEST env, safely back to user.

// without this, control-flow would return to the QuEST backend and likely

// cause internal integrity checks to fail, or segmentation faults

throw std::runtime_error(std::string(errFunc) + ": " + std::string(errMsg));

}

void myErrorHandlerB(const char* errFunc, const char* errMsg) {

std::string func(errFunc);

std::string msg(errMsg);

std::cout

<< "Function '" << func << "' threw '" << msg << "'."

<< std::endl

<< "We will now exit completely. Good day!"

<< std::endl

<< std::endl;

exit(0);

}

int main() {

initQuESTEnv();

setQuESTInputErrorHandler(myErrorHandlerA);

try {

Qureg qureg = createQureg(-123);

} catch (std::runtime_error& e) {

std::cout

<< "Error caught! Function aborted, but execution continues."

<< std::endl

<< std::endl;

}

setQuESTInputErrorHandler(myErrorHandlerB);

initQuESTEnv(); // illegal to recall

std::cout << "this will never be reached, because myErrorHandlerB exits!" << std::endl;

finalizeQuESTEnv();

}