Try to get I18n working

An unsuccessful attempt at getting i18n working through Shakespeare. Had
a little help from:

https://gist.github.com/nicolashery/f87467fb37da2b00cec1eed028f51e60

Unfortunately, I can't figure out how to get this working. Even before,
without the locale stuff and defining a custom `translate` function,
when I tried using Shakespeare's `_{}` function, I was, and still am,
getting this error:

    src/Plugin/GitHubCommit.hs:38:29: error:
        Data constructor not in scope: MsgGitHubCommitRepoURLNotFound

Yes, obviously, that makes sense. But how do I get it to be in scope if
it isn't even in my code? What?

I'm giving up on Shakespeare for i18n. It was a nice idea, I liked the
fact that strings were stored in external files, but I don't know how to
do this, I can't find the right resources online to use this in a
non-web non-template context, and it's becoming a pain. Going to get rid
of all this code and just use regular Haskell data types to do it as
described in
https://wiki.haskell.org/Internationalization_of_Haskell_programs

1 files changed, 19 insertions, 2 deletions

diff --git a/src/I18n.hs b/src/I18n.hs
index 9b9f870..988c823 100644
--- a/src/I18n.hs
+++ b/src/I18n.hs
@@ -1,13 +1,30 @@
+{-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE TemplateHaskell #-}
 
-module I18n where
+module I18n
+    ( Locale(..)
+    , RenderMessage
+
+    , mkMessage
+    , translate
+    ) where
 
 import qualified Data.Text as T
 
-import Text.Shakespeare.I18N (mkMessage, renderMessage)
+import Text.Shakespeare.I18N (mkMessage, renderMessage, RenderMessage)
 
 data Bot = Bot
 
+data Locale = EN | FR
+
+toISOLocale :: Locale -> T.Text
+toISOLocale EN = "en"
+toISOLocale FR = "fr"
+
 mkMessage "Bot" "messages" "en"
+
+translate :: (RenderMessage Bot b) => Locale -> b -> T.Text
+translate locale message =
+    renderMessage Bot [(toISOLocale locale)] message