#pragma once
#include <wtf/Expected.h>
namespace WebCore {
enum class CallbackResultType {
Success,
ExceptionThrown,
UnableToExecute
};
template<typename ReturnType> class CallbackResult {
public:
CallbackResult(CallbackResultType);
CallbackResult(ReturnType&&);
CallbackResultType type() const;
ReturnType&& releaseReturnValue();
private:
Expected<ReturnType, CallbackResultType> m_value;
};
template<> class CallbackResult<void> {
public:
CallbackResult() = default;
CallbackResult(CallbackResultType);
CallbackResultType type() const;
private:
CallbackResultType m_type = CallbackResultType::Success;
};
template<typename ReturnType> inline CallbackResult<ReturnType>::CallbackResult(CallbackResultType type)
: m_value(makeUnexpected(type))
{
}
template<typename ReturnType> inline CallbackResult<ReturnType>::CallbackResult(ReturnType&& returnValue)
: m_value(WTFMove(returnValue))
{
}
template<typename ReturnType> inline CallbackResultType CallbackResult<ReturnType>::type() const
{
return m_value.has_value() ? CallbackResultType::Success : m_value.error();
}
template<typename ReturnType> inline auto CallbackResult<ReturnType>::releaseReturnValue() -> ReturnType&&
{
ASSERT(m_value.has_value());
return WTFMove(m_value.value());
}
inline CallbackResult<void>::CallbackResult(CallbackResultType type)
: m_type(type)
{
}
inline CallbackResultType CallbackResult<void>::type() const
{
return m_type;
}
}