\begin{code}
module Constants (module Constants) where
+import Data.Bits (shiftL)
+
-- This magical #include brings in all the everybody-knows-these magic
-- constants unfortunately, we need to be *explicit* about which one
-- we want; if we just hope a -I... will get the right one, we could
wORD_SIZE_IN_BITS = wORD_SIZE * 8 :: Int
\end{code}
+Amount of pointer bits used for semi-tagging constructor closures
+
+\begin{code}
+tAG_BITS = (TAG_BITS :: Int)
+tAG_MASK = ((1 `shiftL` tAG_BITS) - 1) :: Int
+mAX_PTR_TAG = tAG_MASK :: Int
+\end{code}
+
Size of a C int, in bytes. May be smaller than wORD_SIZE.
\begin{code}