Mac OS X

There is also now the Mac OS X Strike Force that aims to improve using Haskell on OS X.

The Haskell Platform

There are Mac OS X installers of the full Haskell Platform development environment. We recommend it:

GHC

Important notes

To get the most out of your GHC environment, you should add '~/Library/Haskell/bin' to your PATH environment variable before the path where you have GHC installed. This will allow you to get and use cabal-updates, as well as other programs shipped with GHC like hsc2hs.

In your ~/.profile, add the line:

export PATH=$HOME/Library/Haskell/bin:$PATH

Mac OS X 10.9 (Mavericks), Mac OS X 10.8 (Mountain Lion) and Xcode 5

Both Mountain Lion and Mavericks support and now use XCode 5, which no longer provides GCC, only Clang.

This should not be problem for GHC 7.8 and newer, but
If using GHC 7.6.*  or older, one of several work arounds is needed!

The workaround that the Haskell Platform maintainers are supporting can be found here. That work around along with this one work with only the system provided compilers.

However, if you are still encountering usual bugs, the GCC based directions here may work out better.

Mac OS X 10.5 (Leopard)

To install GHC on Mac OS X 10.5 (Leopard), there are the following options:

• install the Haskell Platform
• install MacPort's ghc package

Mac OS X 10.6 (Snow Leopard) and 10.7 (Lion)

• Install the Haskell Platform

To uninstall ghc call: sudo uninstall-hs

Xcode 4.1

GHC needs Xcode to be installed so it has access to the bintools, headers, and link libraries of the platform. The later two are provided by the SDK that comes as part of Xcode. GHC 7.0.2 is compiled against the 10.5 SDK. Xcode 4.1 no longer ships with it. ghci will work, but linking and some compiles with <ghc> will not. To make those work you need a copy of the 10.5 SDK. You can get this one several ways:

• Before you install Xcode 4.1, if you have Xcode 3.2 installed, do one of the following:
  • Move it aside (renaming /Developer to /Xcode3.2)
  • Move just the sdk aside (moving /Developer/SDKs/MacOSX10.5.sdk to, say, /ExtraSDKs/MacOSX10.5.sdk)
  • Move just the sdk aside, install Xcode 4.1, then move it back into the /Developer/SDKs directory.
• If you don't have Xcode 3.2, then you can download it from the Apple Developer site, and install it in a location other than "/Developer". If you have already installed Xcode 4.1 be sure that you customized the install and don't install the "System Tools" or "UNIX Development" packages.

Building via GHC:

ghc --make -I{loc}/MacOSX10.5.sdk/usr/include/ -L{loc}/MacOSX10.5.sdk/usr/lib

Building via cabal:

cabal --extra-include-dirs={loc}/MacOSX10.5.sdk/usr/include/ --extra-lib-dirs={loc}/MacOSX10.5.sdk/usr/lib

Replace {loc} with wherever you put the SDK.

HUGS

• install MacPort's hugs98 package.

Installing libraries with external C bindings

Haskell libraries are installed with the cabal command line tool.

Some libraries depend on external C libraries, which are best installed with MacPorts. However, you have to tell cabal to include the /opt/local/ directories when searching for external libraries. The following shell script does that by wrapping the cabal utility

   > cat cabal-macports
   #!/bin/bash
   export CPPFLAGS=-I/opt/local/include
   export LDFLAGS=-L/opt/local/lib
   cabal $@ --extra-include-dirs=/opt/local/include \
            --extra-lib-dirs=/opt/local/lib

   > cabal-macports install foobar

Editors with Haskell support

Open Source

• AquaMacs or EmacsForOSX, a graphical Emacs version
• Eclipse with the EclipseFP plugin. See EclipseOn_Mac_OS_X
• Emacs, is installed on every Mac
• Leksah
• MacVim, a graphical Vim version
• Textmate 2, open source incarnation of TextMate 1.
• Vim, is installed on every Mac
• Yi (written in Haskell itself!), is available through cabal-install

Commercial

SubEthaEdit:

TextMate:

Smultron:

and Sublime Text 2:

TextEdit is Mac's default text editor, a very basic editor that works fine for most uses, you must however be careful to put it into plain text mode using the Format menu.

Shipping Installable Haskell Applications

• mkbndl builds installable Mac OSX applications from your Haskell project.

Links

• Using Haskell in an Xcode Cocoa project; a description of how to add a Haskell module (callable from C) to an Xcode/Cocoa/Interface builder project on your Mac.
• Mac OS X Common Installation Paths: an effort to standardize where things go on a Mac OS X installation