Simple string substitution library that supports "$"-based
substitution. Meant to be used when Text.Printf or string
concatenation would lead to code that is hard to read but when a full
blown templating system is overkill.
Usage example:
{-# LANGUAGE OverloadedStrings #-}
module Main where
import qualified Data.ByteString.Lazy as S
import qualified Data.Text as T
import qualified Data.Text.Lazy.Encoding as E
import Data.Text.Template
-- | Create 'Context' from association list.
context :: [(T.Text, T.Text)] -> Context
context assocs x = maybe err id . lookup x $ assocs
where err = error $ "Could not find key: " ++ T.unpack x
main :: IO ()
main = S.putStr $ E.encodeUtf8 $ substitute helloTemplate helloContext
where
helloTemplate = "Hello, $name!\n"
helloContext = context [("name", "Joe")]