Approximation Approximator::find(const UnaryRelation& pos,
const UnaryRelation& neg,
const Approximation& arg) {
if (arg.ob and pos.find(arg.ob)) {
return truthy();
} else if (arg.ob and neg.find(arg.ob)) {
return falsey();
} else {
return maybe();
}
}
Approximation Approximator::find(const BinaryRelation& pos,
const BinaryRelation& neg,
const Approximation& lhs,
const Approximation& rhs) {
if (lhs.ob and rhs.ob and pos.find(lhs.ob, rhs.ob)) {
return truthy();
} else if (lhs.ob and rhs.ob and neg.find(lhs.ob, rhs.ob)) {
return falsey();
} else {
return maybe();
}
}
int falsep(object_t obj) {
return truthy(obj) ? 0 : 1;
}
int main (int argc, char ** argv)
{
handle_arguments (argc, argv);
mk::KnowledgeRecord truthy (mk::KnowledgeRecord::Integer (42));
mk::KnowledgeRecord falsey (mk::KnowledgeRecord::Integer (0));
mk::KnowledgeRecord struthy ("true");
mk::KnowledgeRecord sfalsey ("");
if(truthy)
{
std::cout << "SUCCESS truthy is true" << std::endl;
}
else
{
std::cout << "ERROR truthy is false" << std::endl;
}
if(falsey)
{
std::cout << "ERROR falsey is true" << std::endl;
}
else
{
std::cout << "SUCCESS falsey is false" << std::endl;
}
if(truthy && struthy)
{
std::cout << "SUCCESS truthy && struthy is true" << std::endl;
}
else
{
std::cout << "ERROR truthy && struthy is false" << std::endl;
}
if(truthy && sfalsey)
{
std::cout << "ERROR truthy && sfalsey is true" << std::endl;
}
else
{
std::cout << "SUCCESS truthy && sfalsey is false" << std::endl;
}
if(truthy || struthy)
{
std::cout << "SUCCESS truthy || sfalsey is true" << std::endl;
}
else
{
std::cout << "ERROR truthy || sfalsey is false" << std::endl;
}
// These lines compile OK, and work as expected:
bool bool_false = falsey;
bool bool_true = truthy;
if(bool_true)
{
std::cout << "SUCCESS bool_true is true" << std::endl;
}
else
{
std::cout << "ERROR bool_true is false" << std::endl;
}
if(bool_false)
{
std::cout << "ERROR bool_false is true" << std::endl;
}
else
{
std::cout << "SUCCESS bool_false is false" << std::endl;
}
// The following lines should cause compile errors if uncommented:
// naive operator bool() would compile the following:
//int bad_int = truthy; // bad_int would unexpectedly have 1, not 42
//int bad_shift = truthy << 3;
// naive Safe Bool returning void* would compile the following:
//delete truthy;
return 0;
}
void macros_and_constexprs(int i = 0) {
bool b = (i == 1);
if (b && truthy()) {
// leave this alone; if you want it simplified, then you should
// inline the constexpr function first.
i = 1;
}
i = 2;
if (b && HAS_XYZ_FEATURE) {
// leave this alone; if you want it simplified, then you should
// inline the macro first.
i = 3;
}
i = 4;
}
