$THROW ENABLE
$MESSAGE NotFound
@ path std::string const &
"not found: {$path}"

[[noreturn]] void ThrowNotFound( std::string const & path, std::locale const &loc );
[[noreturn]] void ThrowNotFound( std::string const & path );

void ThrowNotFound( std::string const & path )
{
  throw NotFoundException( path );
}

The exception class is generated for $THROW even when $EXCEPTION is disabled; its name, base and OVERRIDE come from the $EXCEPTION settings. A $THROW locale overload makes sure the exception has a constructor taking the locale.