From b532a967e06f644d93af9afe732cfdc3120dc327 Mon Sep 17 00:00:00 2001
From: Jens Petersen <petersen@redhat.com>
Date: Thu, 19 Mar 2020 18:53:13 +0800
Subject: [PATCH] allow building with modern ghc versions

- allow parsec3
- drop old-locale
- stack init for lts-9 (which still had readline)
---
 husky.cabal          | 16 ++++++++++++++--
 src/InfoRoutines.hs  |  1 -
 src/TokenParser.hs   |  5 +++++
 src/UnitConverter.hs |  2 +-
 stack.yaml           |  1 +
 5 files changed, 21 insertions(+), 4 deletions(-)
 create mode 100644 stack.yaml

diff --git a/husky.cabal b/husky.cabal
index 0f10a6e..79e0db6 100644
--- a/husky.cabal
+++ b/husky.cabal
@@ -18,8 +18,20 @@ extra-source-files: README
 
 Executable husky
   Build-Depends:  base, readline >= 1.0.1.0, containers >= 0.1.0.0,
-                  parsec == 2.1.*, mtl >= 1.1.0.0, 
-                  old-locale >= 1.0.0.0, time >= 1.0.0.0
+                  parsec, mtl >= 1.1.0.0,
+                  time >= 1.0.0.0
   ghc-options:    -O2
   Main-Is:        husky.hs
   hs-source-dirs: src
+  other-modules:  CalculatorParser
+                  CalculatorState
+                  ErrorParser
+                  ExtraFunctions
+                  HelpParser
+                  InfoRoutines
+                  Messages
+                  Parser
+                  PrettyPrint
+                  TokenParser
+                  UnitConversionParser
+                  UnitConverter
diff --git a/src/InfoRoutines.hs b/src/InfoRoutines.hs
index e63d1e3..4068090 100644
--- a/src/InfoRoutines.hs
+++ b/src/InfoRoutines.hs
@@ -34,7 +34,6 @@ import Data.Map
 import Data.Time
 import Prelude
 import System.IO
-import System.Locale
 
 
 -- local imports
diff --git a/src/TokenParser.hs b/src/TokenParser.hs
index 79f844e..38970f9 100644
--- a/src/TokenParser.hs
+++ b/src/TokenParser.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 {-----------------------------------------------------------------
  
   (c) 2008-2009 Markus Dittrich 
@@ -61,6 +63,8 @@ import ExtraFunctions
 
 
 
+#if (defined(MIN_VERSION_parsec) && MIN_VERSION_parsec(3,0,0))
+#else
 {- Definitions for Applicative Parsec instance -}
 
 -- | Applicative instance for Monad
@@ -73,6 +77,7 @@ instance Applicative (GenParser s a) where
 instance Alternative (GenParser s a) where
   empty = mzero
   (<|>) = mplus
+#endif
 
 
 
diff --git a/src/UnitConverter.hs b/src/UnitConverter.hs
index 0c78b15..d4f6efd 100644
--- a/src/UnitConverter.hs
+++ b/src/UnitConverter.hs
@@ -78,7 +78,7 @@ convert_unit value unit1 unit2 unitType =
 -- | helper function looking through all unit maps for a matching
 -- conversion routine
 unit_lookup :: String -> M.Map String UnitMap -> [UnitConverter]
-unit_lookup key = M.fold append_val [] 
+unit_lookup key = M.foldr append_val []
    where
      append_val entry acc = case M.lookup key entry of
                               Nothing -> acc
diff --git a/stack.yaml b/stack.yaml
new file mode 100644
index 0000000..7667535
--- /dev/null
+++ b/stack.yaml
@@ -0,0 +1 @@
+resolver: lts-9.21