add conversion from number to church numeral

lambda-calculator.cabal

--- This file has been generated from package.yaml by hpack version 0.21.2.
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.33.0.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: f7f43eaf08f4a2a78ad4d303404ea19c729aa53a0afa30fd0f99d8eb505b8306
+-- hash: 3027a1ad5b882123e9547c30e72a7f9fa49104af48efc12d5e7817927129e600
 
 name:           lambda-calculator
 version:        2.0.0
@@ -17,7 +19,6 @@ copyright:      2016 Sean Gillespie
 license:        MIT
 license-file:   LICENSE
 build-type:     Simple
-cabal-version:  >= 1.10
 
 source-repository head
   type: git

src/Language/Lambda/Parser.hs

@@ -51,3 +51,18 @@ symbol = void . lexeme . char
 
 keyword :: String -> Parser ()
 keyword = void . lexeme . string
+
+ubahKeChurch :: Char -> [Char]
+ubahKeChurch '+' = "(\\w y x. y (w y x))"
+ubahKeChurch '*' = "(\\x y z . x (y z))"
+ubahKeChurch '0' = "(\\s z. z)"
+ubahKeChurch '1' = "(\\s z. s z)"
+ubahKeChurch '2' = "(\\s z. s (s z))"
+ubahKeChurch '3' = "(\\s z. s (s (s z)))"
+ubahKeChurch '4' = "(\\s z. s (s (s (s z))))"
+ubahKeChurch '5' = "(\\s z. s (s (s (s (s z)))))"
+ubahKeChurch '6' = "(\\s z. s (s (s (s (s (s z))))))"
+ubahKeChurch '7' = "(\\s z. s (s (s (s (s (s (s z)))))))"
+ubahKeChurch '8' = "(\\s z. s (s (s (s (s (s (s (s z))))))))"
+ubahKeChurch '9' = "(\\s z. s (s (s (s (s (s (s (s (s z)))))))))"
+ubahKeChurch x = [x]

stack.yaml.lock

+# This file was autogenerated by Stack.
+# You should not edit this file by hand.
+# For more information, please see the documentation at:
+#   https://docs.haskellstack.org/en/stable/lock_files
+
+packages:
+- completed:
+    hackage: Shellac-0.9.9@sha256:3ffcc6aa147ae304774ddde0cd56e92f8d913f12d2e4a7d7fc0e66b7019007db,1984
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+      size: 918
+      sha256: 3c976e2387a598452163f65a14b2cce9f2ffe0e5cc15e15ada173d34cbcdc465
+  original:
+    hackage: Shellac-0.9.9
+- completed:
+    hackage: Shellac-haskeline-0.2.1@sha256:c0fe9917222253f24738fe1feda8150625a4b5034bb21757ae8eba8d92760a10,1052
+    pantry-tree:
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+      sha256: 4f98a09ec110da209e58f809b7015448426430014fbd1d15366809a94b3533b9
+  original:
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+snapshots:
+- completed:
+    size: 567342
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/10/3.yaml
+    sha256: b3d22b89ec630597ad007088e98aa1c8d04844b6c0f23970b513a2862e0b8f0a
+  original: lts-10.3