derive generic instance of Position (#87)

Author: shmish111

bower.json

@@ -29,7 +29,8 @@
     "purescript-maybe": "^4.0.0",
     "purescript-strings": "^4.0.0",
     "purescript-transformers": "^4.1.0",
-    "purescript-unicode": "^4.0.0"
+    "purescript-unicode": "^4.0.0",
+    "purescript-generics-rep": "^6.1.1"
   },
   "devDependencies": {
     "purescript-assert": "^4.0.0",

spago.dhall

@@ -3,6 +3,7 @@
   [ "arrays"
   , "assert"
   , "console"
+  , "generics-rep"
   , "effect"
   , "either"
   , "foldable-traversable"

src/Text/Parsing/Parser/Pos.purs

@@ -1,6 +1,7 @@
 module Text.Parsing.Parser.Pos where
 
 import Prelude
+import Data.Generic.Rep (class Generic)
 import Data.Foldable (foldl)
 import Data.Newtype (wrap)
 import Data.String (split)
@@ -14,6 +15,8 @@ newtype Position = Position
   , column :: Int
   }
 
+derive instance genericPosition :: Generic Position _
+
 instance showPosition :: Show Position where
   show (Position { line: line, column: column }) =
     "(Position { line: " <> show line <> ", column: " <> show column <> " })"