improve Slice

include/avian/util/assert.h

@@ -0,0 +1,32 @@
+/* Copyright (c) 2008-2013, Avian Contributors
+
+   Permission to use, copy, modify, and/or distribute this software
+   for any purpose with or without fee is hereby granted, provided
+   that the above copyright notice and this permission notice appear
+   in all copies.
+
+   There is NO WARRANTY for this software.  See license.txt for
+   details. */
+
+#ifndef AVIAN_UTIL_ASSERT_H
+#define AVIAN_UTIL_ASSERT_H
+
+#include <stdlib.h>
+
+namespace avian {
+namespace util {
+
+#define UNREACHABLE_ ::abort()
+
+// TODO: print msg in debug mode
+#define UNREACHABLE(msg) ::abort()
+
+#define ASSERT(that)    \
+  if (!(that)) {        \
+    UNREACHABLE(#that); \
+  }
+
+}  // namespace util
+}  // namespace avian
+
+#endif  // AVIAN_UTIL_ASSERT_H