make an explicit configure flag for the vty ui

Makefile

@@ -2,8 +2,9 @@
 BENCHEXES=hledger ledger
 
 BUILD=ghc --make hledger.hs -o hledger -O
+BUILDFLAGS=-DVTY
 build: tag
-	$(BUILD)
+	$(BUILD) $(BUILDFLAGS)
 
 BUILDO2=ghc --make hledger.hs -o hledgero2 -O2 -fvia-C
 buildo2:
@@ -15,8 +16,9 @@ rebuild: clean build
 # recompile and run tests whenever a module changes
 # see http://searchpath.org , you may need the patched version from
 # http://joyful.com/repos/searchpath
+CICMD=test
 continuous ci:
-	sp --no-exts --no-default-map -o hledger ghc --make hledger.hs --run test
+	sp --no-exts --no-default-map -o hledger ghc --make hledger.hs $(BUILDFLAGS) --run $(CICMD)
 
 # run code tests
 test:

README

@@ -29,8 +29,17 @@ http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hledger and do::
  sudo runhaskell Setup.hs install 
 
 This will complain about any missing libraries, which you can download and
-install manually from hackage.haskell.org. (The Build-Depends: in
-hledger.cabal has the full package list.)
+install manually from hackage.haskell.org. The Build-Depends: in
+hledger.cabal has the full package list. 
+
+You can configure with optional flags to build additional hledger
+features. These are::
+
+  -f vty   - Build vty-based text ui (requires vty, not available on windows)
+
+Eg::
+
+ cabal install -f "vty" hledger (or runhaskell Setup.hs configure -f "vty")
 
 To get the latest development code do::
 

hledger.cabal

@@ -17,16 +17,13 @@ License-File:   LICENSE
 Extra-Source-Files: README sample.ledger
 Extra-Tmp-Files: 
 Cabal-Version:  >= 1.2
+Flag vty
+  description: Build vty-based text ui (requires vty, not available on windows)
+  default:     False
 
 Executable hledger
   Main-Is:        hledger.hs
-
-  if !os(windows)
-    Build-Depends:vty>=3.1.8.2
-    Other-Modules:UICommand
-
-  Build-Depends:  
-                  base,
+  Build-Depends:  base,
                   containers, 
                   haskell98, 
                   directory, 
@@ -38,8 +35,7 @@ Executable hledger
                   HUnit, 
                   mtl, 
                   bytestring
-  Other-Modules:  
-                  BalanceCommand
+  Other-Modules:  BalanceCommand
                   Options
                   PrintCommand
                   RegisterCommand
@@ -61,12 +57,15 @@ Executable hledger
                   Ledger.Transaction
                   Ledger.Types
                   Ledger.Utils
+  if flag(vty)
+    Build-Depends:vty>=3.1.8.2
+    Other-Modules:UICommand
+    cpp-options: -DVTY
 
-library
+Library
   Build-Depends:  base, containers, haskell98, directory, parsec, regex-compat,
                   old-locale, time, HUnit
-  Exposed-modules:
-                  Ledger
+  Exposed-modules:Ledger
                   Ledger.Account
                   Ledger.AccountName
                   Ledger.Amount

hledger.hs

@@ -40,10 +40,6 @@ module Main (
              module BalanceCommand,
              module PrintCommand,
              module RegisterCommand,
-#ifndef mingw32_HOST_OS
--- the ui command requires vty which is not available on windows
-             module UICommand,
-#endif
 )
 where
 import Control.Monad.Error
@@ -56,8 +52,8 @@ import Options
 import BalanceCommand
 import PrintCommand
 import RegisterCommand
-#ifndef mingw32_HOST_OS
-import UICommand
+#ifdef VTY
+import qualified UICommand
 #endif
 import Tests
 
@@ -73,8 +69,8 @@ main = do
        | cmd `isPrefixOf` "balance"  = parseLedgerAndDo opts args balance
        | cmd `isPrefixOf` "print"    = parseLedgerAndDo opts args print'
        | cmd `isPrefixOf` "register" = parseLedgerAndDo opts args register
-#ifndef mingw32_HOST_OS
-       | cmd `isPrefixOf` "ui"       = parseLedgerAndDo opts args ui
+#ifdef VTY
+       | cmd `isPrefixOf` "ui"       = parseLedgerAndDo opts args UICommand.ui
 #endif
        | cmd `isPrefixOf` "test"     = runtests opts args >> return ()
        | otherwise                   = putStr $ usage