Main.hs

-- Object (fromList [("paging_info",Object (fromList [("page_count",Number 1.0),("current_page",Number 1.0),("entity_count",Number 1.0),("entities_per_page",Number 1.0)])),("entities",Array [Object (fromList [("id",Number 4482.0),("type",String "HumanUser"),("login",String "person")])])])

findOne :: (ToJSON a, FromJSON b, AsValue b) => a -> App b
findOne sParams = do
  r <- postShotgun sParams
  let r' = r ^? nth 0 . key "entities" . _Array . nth 0
  return r
  
--    Could not deduce (AsValue (Vector Value))
--      arising from a use of ‘nth’
--    from the context (ToJSON a, FromJSON b, AsValue b)
--      bound by the type signature for
--                 findOne :: (ToJSON a, FromJSON b, AsValue b) => a -> App b
--      at src/Lib/Wreq.hs:55:12-58
--    In the second argument of ‘(.)’, namely ‘nth 0’
--    In the second argument of ‘(.)’, namely ‘_Array . nth 0’
--    In the second argument of ‘(.)’, namely
--      ‘key "entities" . _Array . nth 0’