source: tests/exceptions/defaults.cfa @ 0ebbca4

// Tests for providing new default operations.

#include <string.h>
#include <exception.hfa>

exception log_message {
        char * msg;
};

_EHM_DEFINE_COPY(log_message, )
const char * msg(log_message * this) {
        return this->msg;
}
_EHM_VIRTUAL_TABLE(log_message, , log_vt);

// Logging messages don't have to be handled.
void defaultResumptionHandler(log_message &) {}

// And should never be used to terminate computation.
void defaultTerminationHandler(log_message &) = void;

void log_test(void) {
        // We can catch log:
        try {
                throwResume (log_message){&log_vt, "Should be printed.\n"};
        } catchResume (log_message * this) {
                printf("%s", this->virtual_table->msg(this));
        }
        // But we don't have to:
        throwResume (log_message){&log_vt, "Should not be printed.\n"};
}

// I don't have a good use case for doing the same with termination.
exception jump {};
void defaultTerminationHandler(jump &) {
        printf("jump default handler.\n");
}

vtable(jump) jump_vt;

void jump_test(void) {
        try {
                throw (jump){&jump_vt};
        } catch (jump * this) {
                printf("jump catch handler.\n");
        }
        throw (jump){&jump_vt};
}

exception first {};
vtable(first) first_vt;

exception unhandled_exception {};
vtable(unhandled_exception) unhandled_vt;

void unhandled_test(void) {
        forall(T &, V & | is_exception(T, V))
        void defaultTerminationHandler(T &) {
                throw (unhandled_exception){&unhandled_vt};
        }
        void defaultTerminationHandler(unhandled_exception &) {
                abort();
        }
        try {
                throw (first){&first_vt};
        } catch (unhandled_exception * t) {
                printf("Catch unhandled_exception.\n");
        }
}

exception second {};
vtable(second) second_vt;

void cross_test(void) {
        void defaultTerminationHandler(first &) {
                printf("cross terminate default\n");
                throw (second){&second_vt};
        }
        void defaultResumptionHandler(first &) {
                printf("cross resume default\n");
                throwResume (second){&second_vt};
        }
        try {
                printf("cross terminate throw\n");
                throw (first){&first_vt};
        } catch (second *) {
                printf("cross terminate catch\n");
        }
        try {
                printf("cross resume throw\n");
                throwResume (first){&first_vt};
        } catchResume (second *) {
                printf("cross resume catch\n");
        }
}

int main(int argc, char * argv[]) {
        log_test();
        jump_test();
        unhandled_test();
        cross_test();
}