Error checking in function that returns reference to static variable

Question

This is a function I just wrote with the goal to only load the desired information once, and if an error occurs, save it for later so that it can always be reported to a calling function.

It does what I want but seems quite clumsy.

std::wstring const& GetMuiFilePath()
{
 static DWORD error = NO_ERROR;
 static std::wstring muiPath;
 static bool hasTriedLoadingPath = false;
 if (!hasTriedLoadingPath) {
 try {
 muiPath = Internal::zGetSpecialFolder(zCsidlSystem)
 + L"\\" + Internal::zGetSystemLocale()
 + L"\\" + L"wbadmin.exe.mui";
 }
 catch (AutoWinError const& e) {
 error = e.m_error;
 }
 hasTriedLoadingPath = true;
 }
 if (muiPath.empty()) {
 throw AutoWinError(error);
 }
 return muiPath;
}

Answer 1

The only things I would change are:

 // Move this boolean to the top.
 // So if you throw an exception that is not caught
 // you then stil know that you have tried.
 hasTriedLoadingPath = true;
 try {
 // No change.
 muiPath = Internal::zGetSpecialFolder(zCsidlSystem)
 + L"\\" + Internal::zGetSystemLocale()
 + L"\\" + L"wbadmin.exe.mui";
 }
 catch (AutoWinError const& e) {
 error = e.m_error;
 // Curious why you did not re-do the throw here?
 throw; // Note. Not `throw e;`
 // Rethrows the current exception.
 }