From 062cd0415af4d5365d314d345a7604a10b650b7a Mon Sep 17 00:00:00 2001
From: Neil Brown <neil@twistedsquare.com>
Date: Sun, 24 Feb 2008 12:15:39 +0000
Subject: [PATCH] Added a simple (-h/--help) option for printing the Tock help

---
 Main.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Main.hs b/Main.hs
index bb151c1..35995a1 100644
--- a/Main.hs
+++ b/Main.hs
@@ -58,6 +58,7 @@ options =
   [ Option [] ["mode"] (ReqArg optMode "MODE") "select mode (options: flowgraph, parse, compile, post-c, full)"
   , Option [] ["backend"] (ReqArg optBackend "BACKEND") "code-generating backend (options: c, cppcsp, dumpast)"
   , Option [] ["frontend"] (ReqArg optFrontend "FRONTEND") "language frontend (options: occam, rain)"
+  , Option ['h'] ["help"] (NoArg optPrintHelp) "print this help"
   , Option ['v'] ["verbose"] (NoArg $ optVerbose) "be more verbose (use multiple times for more detail)"
   , Option ['o'] ["output"] (ReqArg optOutput "FILE") "output file (default \"-\")"
   , Option [] ["usage-checking"] (ReqArg optUsageChecking "SETTING") "usage checking (EXPERIMENTAL) (options: on, off)"
@@ -98,6 +99,9 @@ optVerbose ps = return $ ps { csVerboseLevel = csVerboseLevel ps + 1 }
 optOutput :: String -> OptFunc
 optOutput s ps = return $ ps { csOutputFile = s }
 
+optPrintHelp :: OptFunc
+optPrintHelp _ = dieIO (Nothing, usageInfo "Usage: tock [OPTION...] SOURCEFILE" options)
+
 optUsageChecking :: String -> OptFunc
 optUsageChecking s ps
     =  do usageCheck <- case s of