Also added a pretty much untested and totally incomplete STL string type.

bastl/include/exception

@@ -0,0 +1,50 @@
+
+#if !defined(BAD_APPLE_OS_EXCEPTION_INCLUDED)
+#define BAD_APPLE_OS_EXCEPTION_INCLUDED
+
+#include <cstdlib>
+#include "os/panic.hpp"
+
+#if defined(__cpp_exceptions)
+#define __ba_throw throw
+#else
+#define __ba_throw ba::impl::gAbortHelper(__FILE__, __LINE__) =
+#endif
+
+namespace std
+{
+class exception
+{
+public:
+    virtual ~exception() noexcept = default;
+    virtual const char* what() const noexcept;
+};
+}
+
+#if !defined(__cpp_exceptions)
+namespace ba::impl
+{
+struct ExceptionAbortHelper
+{
+private:
+    const char* mFile = "<unknown>";
+    int mLine = -1;
+public:
+    [[noreturn]] ExceptionAbortHelper& operator=(const std::exception& ex) noexcept
+    {
+        panicf("Uncaught exception with message \"%s\" at %s:%d.", ex.what(), mFile, mLine);
+    }
+
+    ExceptionAbortHelper& operator()(const char* file, int line) noexcept
+    {
+        mFile = file;
+        mLine = line;
+        return *this;
+    }
+};
+
+extern ExceptionAbortHelper gAbortHelper;
+}
+#endif // !defined(__cpp_exceptions)
+
+#endif // !defined(BAD_APPLE_OS_EXCEPTION_INCLUDED)