From b76aa73bc76a28d7c6bb3c5a43acc9afd9ec42c8 Mon Sep 17 00:00:00 2001 From: Joel Martin Date: Tue, 23 Dec 2014 20:35:48 -0700 Subject: Haskell: steps 0-3 --- haskell/Printer.hs | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 haskell/Printer.hs (limited to 'haskell/Printer.hs') diff --git a/haskell/Printer.hs b/haskell/Printer.hs new file mode 100644 index 0000000..94bc5ed --- /dev/null +++ b/haskell/Printer.hs @@ -0,0 +1,36 @@ +module Printer +( _pr_str ) +where + +import qualified Data.Map as Map + +import Types + +_pr_list :: [MalVal] -> String +_pr_list = unwords . map _pr_str + +_flatTuples ((a,b):xs) = MalString a : b : _flatTuples xs +_flatTuples _ = [] + +unescape chr = case chr of + '\n' -> "\\n" + '\\' -> "\\\\" + '"' -> "\\\"" + c -> [c] + +_pr_str :: MalVal -> String +_pr_str (MalString ('\x029e':str)) = ":" ++ str +_pr_str (MalString str) = "\"" ++ concatMap unescape str ++ "\"" +_pr_str (MalSymbol name) = name +_pr_str (MalKeyword name) = ":" ++ name +_pr_str (MalNumber num) = show num +_pr_str (MalTrue) = "true" +_pr_str (MalFalse) = "false" +_pr_str (Nil) = "nil" +_pr_str (MalList items) = "(" ++ _pr_list items ++ ")" +_pr_str (MalVector items) = "[" ++ _pr_list items ++ "]" +_pr_str (MalHashMap m) = "{" ++ _pr_list (_flatTuples $ Map.assocs m) ++ "}" +_pr_str (MalFunc f) = "#" + +instance Show MalVal where show = _pr_str + -- cgit v1.2.3