Added some modest improvements to code.

src/Text/Literate.idr

@@ -62,28 +62,28 @@ rawTokens delims ls =
        ++ [(notCodeLine, Any)]
 
 ||| Merge the tokens into a single source file.
-reduce : List (TokenData Token) -> String -> String
-reduce [] acc = acc
-reduce (MkToken _ _ (Any x) :: rest) acc = reduce rest (acc ++ blank_content)
+reduce : List (TokenData Token) -> List String -> String
+reduce [] acc = fastAppend (reverse acc)
+reduce (MkToken _ _ (Any x) :: rest) acc = reduce rest (blank_content::acc)
   where
     -- Preserve the original document's line count.
     blank_content : String
-    blank_content = if elem '\n' (unpack x)
-      then concat $ replicate (length (lines x)) "\n"
-      else ""
+    blank_content = fastAppend (replicate (length (lines x)) "\n")
+
 reduce (MkToken _ _ (CodeLine m src) :: rest) acc =
     if m == trim src
-    then reduce rest (acc ++ "\n")
-    else reduce rest (acc ++ (substr (length m + 1) -- remove space to right of marker.
-                                     (length src)
-                                     src))
+    then reduce rest ("\n"::acc)
+    else reduce rest ((substr (length m + 1) -- remove space to right of marker.
+                              (length src)
+                              src
+                      )::acc)
 
 reduce (MkToken _ _ (CodeBlock l r src) :: rest) acc with (lines src) -- Strip the deliminators surrounding the block.
   reduce (MkToken _ _ (CodeBlock l r src) :: rest) acc | [] = reduce rest acc -- 1
   reduce (MkToken _ _ (CodeBlock l r src) :: rest) acc | (s :: ys) with (snocList ys)
     reduce (MkToken _ _ (CodeBlock l r src) :: rest) acc | (s :: []) | Empty = reduce rest acc -- 2
     reduce (MkToken _ _ (CodeBlock l r src) :: rest) acc | (s :: (srcs ++ [f])) | (Snoc f srcs rec) =
-        reduce rest (acc ++ "\n" ++ unlines srcs)
+        reduce rest ("\n" :: unlines srcs :: acc)
 
 -- [ NOTE ] 1 & 2 shouldn't happen as code blocks are well formed i.e. have two deliminators.
 
@@ -164,7 +164,7 @@ extractCode : (specification : LiterateStyle)
            -> Either LiterateError String
 extractCode (MkLitStyle delims markers exts) str =
       case lex (rawTokens delims markers) str of
-        (toks, (_,_,"")) => Right $ reduce toks ""
+        (toks, (_,_,"")) => Right (reduce toks Nil)
         (_, (l,c,i))     => Left (MkLitErr l c i)
 
 ||| Synonym for `extractCode`.