quote a module contents with a string literal -- Template Haskell solution

Config.hs

{-# LANGUAGE TemplateHaskell #-}
module Config where
import Language.Haskell.TH
import Data.List.Split (splitOn)
-- START
-- extractCtxs'dumpSize :: Int
-- extractCtxs'dumpSize = 100000
extractCtxs'ctxSize :: Int
extractCtxs'ctxSize = 300
extractCtxs'sparse :: Bool
extractCtxs'sparse = True
selectWords'dropBorder :: Int
selectWords'dropBorder = 20000
selectWords'takeCount :: Int
selectWords'takeCount = 100
-- STOP
config' = $(do
 s <- runIO $ readFile "lib/Config.hs"
 return $ LitE $ stringL s)
config = head . splitOn "-- STOP" . head . tail . splitOn "-- START" $ config'