hatt 0.3 → 1.0

raw patch · 3 files changed

+54/−27 lines, 3 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• README.md +8/−0
• hatt.cabal +1/−1
• src/hatt.hs +45/−26

@@ -51,6 +51,11 @@     help       Print this help text.     +    pretty+      Pretty-print expressions using Unicode logic symbols. Only employ this+      option if your console is Unicode-aware. If pretty-printing is already+      enabled, using this command will disable it.+         exit       Quit the program.     @@ -113,6 +118,9 @@     F T F | F     F F T | T     F F F | F++You can enable pretty-printing while in interactive mode by using the `pretty`+command.   Using Hatt in other programs

@@ -1,5 +1,5 @@ Name:               hatt-Version:            0.3+Version:            1.0 Stability:          experimental  Synopsis:           A truth table generator for classical propositional logic.

@@ -10,32 +10,33 @@ import System.Console.CmdArgs import System.IO -data HattOpts = HattOpts-    { evaluate    :: String-    , interactive :: Bool-    , pretty      :: Bool-    } deriving (Show, Data, Typeable)- data Command = Exit              | Help+             | Pretty              | Eval Expr              | Error String -hattOpts :: HattOpts-hattOpts = HattOpts+data ProgramMode = ProgramMode+  { evaluate    :: String+  , interactive :: Bool+  , pretty      :: Bool+  } deriving (Show, Data, Typeable)++programMode :: ProgramMode+programMode = ProgramMode   { evaluate    = "" &= typ  "EXPRESSION"                      &= help "Print the truth table for the given expression"   , interactive = False &= help "Enter interactive mode"   , pretty      = False &= help "Use Unicode logic symbols"-  } &= summary "Hatt 0.3, (c) Benedict Eastaugh 2011"+  } &= summary "Hatt 1.0, (c) Benedict Eastaugh 2011"     &= program "hatt"  main :: IO ()-main = do opts <- cmdArgs hattOpts+main = do opts <- cmdArgs programMode           let expStr    = evaluate opts               interMode = interactive opts               evalMode  = (not . null) expStr-              printer   = if pretty opts then show else showAscii+              printer   = selectPrinter opts                      -- If the --evaluate flag is passed with an expression, print the           -- truth table for that expression.@@ -48,17 +49,26 @@           -- program; otherwise, enter interactive mode.           if evalMode && not interMode             then return ()-            else putStrLn replIntroText >> repl printer+            else putStrLn replIntroText >> repl opts -repl :: (Expr -> String) -> IO ()-repl p = do putStr "> "-            hFlush stdout-            cmd <- getLine-            case parseCommand cmd of-              Exit        -> return ()-              Help        -> putStr   replHelpText         >> repl p-              (Eval expr) -> putStr   (truthTableP p expr) >> repl p-              (Error err) -> putStrLn ("Error: " ++ err)   >> repl p+repl :: ProgramMode -> IO ()+repl mode = do putStr "> "+               hFlush stdout+               cmd <- getLine+               case parseCommand cmd of+                 Exit        -> return ()+                 Help        -> putStr replHelpText+                                >> repl mode+                 Pretty      -> putStrLn ppMessage+                                >> repl (mode {pretty = not isPretty})+                 (Eval expr) -> putStr (truthTableP printer expr)+                                >> repl mode+                 (Error err) -> putStrLn ("Error: " ++ err)+                                >> repl mode+  where+    printer   = selectPrinter mode+    isPretty  = pretty mode+    ppMessage = (if isPretty then "Dis" else "En") ++ "abling pretty-printing."  eval :: (Expr -> String) -> String -> String eval p str = case parseExpr "" str of@@ -67,10 +77,11 @@  parseCommand :: String -> Command parseCommand input = case cmd . words . dropWhile isSpace $ input of-                       ""     -> Error "you must enter an expression or a command."-                       "exit" -> Exit-                       "help" -> Help-                       _      -> eval_ input+                       ""       -> Error "you must enter an expression or a command."+                       "exit"   -> Exit+                       "help"   -> Help+                       "pretty" -> Pretty+                       _        -> eval_ input   where     cmd []    = ""     cmd ws    = map toLower . head $ ws@@ -86,11 +97,16 @@  replHelpText :: String replHelpText = unlines-  [ "Hatt's interactive mode has a couple of commands."+  [ "Hatt's interactive mode has several commands."   , ""   , "help"   , "  Print this help text."   , ""+  , "pretty"+  , "  Pretty-print expressions using Unicode logic symbols. Only employ this"+  , "  option if your console is Unicode-aware. If pretty-printing is already"+  , "  enabled, using this command will disable it."+  , ""   , "exit"   , "  Quit the program."   , ""@@ -115,3 +131,6 @@   , ""   , "If none of this makes any sense, try reading the README file."   ]++selectPrinter :: ProgramMode -> (Expr -> String)+selectPrinter m = if pretty m then show else showAscii