c++ - std::ostream to QString? -

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is there way convert std::ostream qstring?

allow me expand in case useful: writing program in c++/qt , used (not) deal / debug exceptions using std::cout, in example:

std::cout << "error in void cat::eat(const bird &bird): bird has negative weight" << std::endl;

now want throw errors qstrings , catch them later, write instead:

throw(qstring("error in void cat::eat(const bird &bird): bird has negative weight"));

my issue i've been overloading operator << can use many objects, instance bird, have written:

std::cout << "error in void cat::eat(const bird &bird): bird " << bird << " has negative weight" << std::endl;

is there way can throw qstring now? able write like:

std::ostream out; out << "error in void cat::eat(const bird &bird): bird " << bird << " has negative weight" << std::endl; throw(qstring(out));

but doesn't work. should do?

you can use std::stringstream follows:

std::stringstream out; //   ^^^^^^ out << "error in void cat::eat(const bird &bird): bird " << bird << " has negative weight" << std::endl; throw(qstring::fromstdstring(out.str())); //           ^^^^^^^^^^^^^^^^^^^^^^^^^^

specifically, std::stringstream::str member function std::string, can pass qstring::fromstdstring static member function create qstring.


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