1 files changed, 27 insertions, 0 deletions
diff --git a/third_party/bazel/rules_haskell/examples/vector/tests/Boilerplater.hs b/third_party/bazel/rules_haskell/examples/vector/tests/Boilerplater.hs
new file mode 100644
index 0000000000..5506209ebc
--- /dev/null
+++ b/third_party/bazel/rules_haskell/examples/vector/tests/Boilerplater.hs
@@ -0,0 +1,27 @@
+module Boilerplater where
+
+import Test.Framework.Providers.QuickCheck2
+
+import Language.Haskell.TH
+
+
+testProperties :: [Name] -> Q Exp
+testProperties nms = fmap ListE $ sequence [[| testProperty $(stringE prop_name) $(varE nm) |]
+                                           | nm <- nms
+                                           , Just prop_name <- [stripPrefix_maybe "prop_" (nameBase nm)]]
+
+-- This nice clean solution doesn't quite work since I need to use lexically-scoped type
+-- variables, which aren't supported by Template Haskell. Argh!
+-- testProperties :: Q [Dec] -> Q Exp
+-- testProperties mdecs = do
+--     decs <- mdecs
+--     property_exprs <- sequence [[| testProperty "$prop_name" $(return $ VarE nm) |]
+--                                | FunD nm _clauses <- decs
+--                                , Just prop_name <- [stripPrefix_maybe "prop_" (nameBase nm)]]
+--     return $ LetE decs (ListE property_exprs)
+
+stripPrefix_maybe :: String -> String -> Maybe String
+stripPrefix_maybe prefix what
+  | what_start == prefix = Just what_end
+  | otherwise            = Nothing
+  where (what_start, what_end) = splitAt (length prefix) what