+-- | Filters non-state signals and returns the state number and signal id for
+-- state values.
+filterState ::
+ SignalId -- | The signal id to look at
+ -> HsValueUse -- | How is this signal used?
+ -> Maybe (StateId, SignalId ) -- | The state num and signal id, if this
+ -- signal was used as state
+
+filterState id (State num) =
+ Just (num, id)
+filterState _ _ = Nothing
+
+-- | Returns a list of the state number and signal id of all used-as-state
+-- signals in the given maps.
+stateList ::
+ HsUseMap
+ -> (SignalMap)
+ -> [(StateId, SignalId)]
+
+stateList uses signals =
+ Maybe.catMaybes $ Foldable.toList $ zipValueMapsWith filterState signals uses
+
+-- | Returns pairs of signals that should be mapped to state in this function.
+getOwnStates ::
+ HsFunction -- | The function to look at
+ -> FlatFunction -- | The function to look at
+ -> [(StateId, SignalInfo, SignalInfo)]
+ -- | The state signals. The first is the state number, the second the
+ -- signal to assign the current state to, the last is the signal
+ -- that holds the new state.
+
+getOwnStates hsfunc flatfunc =
+ [(old_num, old_info, new_info)
+ | (old_num, old_info) <- args_states
+ , (new_num, new_info) <- res_states
+ , old_num == new_num]
+ where
+ sigs = flat_sigs flatfunc
+ -- Translate args and res to lists of (statenum, sigid)
+ args = concat $ zipWith stateList (hsFuncArgs hsfunc) (flat_args flatfunc)
+ res = stateList (hsFuncRes hsfunc) (flat_res flatfunc)
+ -- Replace the second tuple element with the corresponding SignalInfo
+ args_states = map (Arrow.second $ signalInfo sigs) args
+ res_states = map (Arrow.second $ signalInfo sigs) res
+
+