// The program demonstrate how to capture an exception thrown
// from a running taskflow
#include <taskflow/taskflow.hpp>

int main(){

 tf::Executor executor;
 tf::Taskflow taskflow("exception");

 auto [A, B, C, D] = taskflow.emplace(
 []() { std::cout << "TaskA\n"; },
 []() { 
 std::cout << "TaskB\n";
 throw std::runtime_error("Exception on Task B");
 },
 []() { 
 std::cout << "TaskC\n"; 
 throw std::runtime_error("Exception on Task C");
 },
 []() { std::cout << "TaskD will not be printed due to exception\n"; }
 );

 A.precede(B, C); // A runs before B and C
 D.succeed(B, C); // D runs after B and C

 try {
 executor.run(taskflow).get();
 }
 catch(const std::runtime_error& e) {
 // catched either TaskB's or TaskC's exception
 std::cout << e.what() << std::endl;
 }

 return 0;
}