Introduce FSTs & Generalize input/output

`toFST` is currently invalid

1 files changed, 24 insertions, 0 deletions

diff --git a/edit-lens/src/Control/FST.lhs b/edit-lens/src/Control/FST.lhs
new file mode 100644
index 0000000..d3c8ca9
--- /dev/null
+++ b/edit-lens/src/Control/FST.lhs
@@ -0,0 +1,24 @@
+\begin{code}
+
+{-|
+Description: Finite state transducers with epsilon-transitions
+-}
+module Control.FST
+  ( FST(..)
+  ) where
+
+import Data.Map.Strict (Map)
+import qualified Data.Map.Strict as Map
+
+import Data.Set (Set)
+
+import Data.Sequence (Seq)
+
+import Control.Lens.TH
+
+data FST state input output = FST
+  { stInitial :: state
+  , stTransition :: Map (state, Maybe input) (Set (state, Maybe output))
+  , stAccept :: Set state
+  }
+\end{code}