guess

guess/guess.cabal

@@ -2,7 +2,7 @@
 --
 -- see: https://github.com/sol/hpack
 --
+-- hash: b0bd48edc90ce1eed0fa5dbe1b4f6f321e28b02044e8d324cfe04b67c5839142
 
 name:           guess
 version:        0.1.0.0
@@ -35,6 +35,7 @@ library
       base >=4.8 && <5
     , protolude
   exposed-modules:
+      Guess
       Lib
   other-modules:
       Paths_guess

guess/package.yaml

@@ -21,8 +21,6 @@ dependencies:
 - protolude
 library:
   source-dirs: src
-  exposed-modules:
-  - Lib
 executables:
   guess-exe:
     main: Main.hs
@@ -69,4 +67,4 @@ benchmarks:
     dependencies:
     - criterion >=1.1
     - guess
-stability: alpha (experimental)
+stability: alpha (experimental)

guess/src-exe/Main.hs

@@ -1,6 +1,8 @@
 import Protolude
 
-import Lib (inc)
+import Guess (guess)
 
 main :: IO ()
-main = print (inc 41)
+main = do
+  guess
+  putText "Bye!"

guess/src/Guess.hs

@@ -0,0 +1,20 @@
+module Guess
+  ( guess
+  ) where
+
+import Protolude
+
+guess :: IO ()
+guess = guessBetween 0 120
+
+guessBetween :: Integer -> Integer -> IO ()
+guessBetween minAge maxAge = do
+  let age = (maxAge + minAge) `div` 2
+  if minAge == maxAge
+    then putText ("You are " <> show age)
+    else do
+      putText ("Are you younger than " <> show age <> "?")
+      answer <- getLine
+      case answer of
+        "y" -> guessBetween minAge (age - 1)
+        _ ->  guessBetween (if age == minAge then age + 1 else age) maxAge

hwp.hsfiles

@@ -22,8 +22,6 @@ dependencies:
 - protolude
 library:
   source-dirs: src
-  exposed-modules:
-  - Lib
 executables:
   {{ name }}-exe:
     main: Main.hs