1 files changed, 14 insertions, 0 deletions
diff --git a/compiler/utils/FreeVarStrategy.hs b/compiler/utils/FreeVarStrategy.hs
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+++ b/compiler/utils/FreeVarStrategy.hs
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+module FreeVarStrategy (FreeVarStrategy(..)) where
+
+import {-# SOURCE #-} TyCoRep (CoercionHole)
+
+import Var
+
+import Data.Monoid (Monoid)
+
+class Monoid m => FreeVarStrategy m where
+  -- | Introduce a free 'CohercionHole'.
+  coholeFV  :: CoercionHole -> m
+  -- | Introduce a free variable (and any free variables of its type/kind).
+  unitFV   :: Var -> m
+  bindVar :: Var -> m -> m