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diff --git a/utils/completion/README b/utils/completion/README
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+========================================
+Glasgow Haskell Compiler Bash Completion
+========================================
+
+Depending on how you've installed GHC, there are different ways to turn
+on the bash completion.  With a bit of luck, your OS distribution has already
+setup everything and it's already working!  But since you're reading this file,
+we assume that was not the case. Read on!
+
+
+Option 1: Using your OS distribution's tools
+--------------------------------------------
+
+This should work if you installed GHC using the package manager of your *nix
+distribution.  You need the 'bash-completion' package from your package manager
+(likely already installed), and something like this in your ~/.bashrc file;
+
+    if [ -f /usr/share/bash-completion/bash_completion ]; then
+      . /usr/share/bash-completion/bash_completion
+    elif [ -f /etc/bash_completion ]; then
+      . /etc/bash_completion
+    fi
+
+When you installed GHC using your OS distribution's package manager it should
+have copied the bash completion file to the right directory.
+Open a new terminal and try it out!
+
+
+Option 2: Without OS distribution support
+-----------------------------------------
+
+Maybe your OS distribution doesn't support GHC's bash completion, maybe
+you've installed your own build of GHC.  In either case, you can still have
+bash completion!  You can even use GHC's bash completion without the
+'bash-completion' package. Here are the steps;
+
+ 1) Copy the ghc.bash file somewhere (eg. ~/ghc.bash) or use it directly from
+    the source directory.
+ 2) Add the following to your ~/.bashrc;
+
+      source ~/ghc.bash
+
+That's it!
diff --git a/utils/completion/ghc.bash b/utils/completion/ghc.bash
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+# ========================================
+# Glasgow Haskell Compiler Bash Completion
+# ========================================
+#
+# For how to use the GHC bash completion, see the README.
+#
+# This file implements bash completion for both GHC and GHCi.
+#
+#  - We use GHC's --show-options to get a list of the available
+#    flags. It is aware that some flags are used for GHC, and others for GHCi.
+#  - We understand when the argument;
+#     * has to be a directory name (eg. following -hidir)
+#     * cannot be completed (eg. following -e)
+#
+# Future work;
+#  - Some flags needs their argument after an equal sign;
+#      eg. -fmax-simplifier-iterations=N
+#      Currently the flag will be completed without knowledge of
+#      the required argument.
+#  - Complete package names/ids.
+#      eg. -package-id <TAB><TAB> should list valid package-ids
+#  - The +RTS flags are not supported.
+#      +RTS <TAB><TAB> should list valid RTS flags.
+
+_ghc ()
+{
+  local completions=`$1 --show-options`
+  local cur="${COMP_WORDS[COMP_CWORD]}"
+  local prev="${COMP_WORDS[COMP_CWORD-1]}"
+
+  # Complete the current flag based on the previous flag.
+  case "$prev" in
+    -hidir|-odir|-stubdir|-dumpdir|-outputdir|-tmpdir|-hpcdir|-dylib-install-name|-framework-path)
+      # Complete only with directory names.
+      compopt -o dirnames
+      return 0
+      ;;
+    -package-name|-package|-hide-package|-ignore-package|-trust|-distrust)
+      # Should complete package names. Not implemented.
+      # To do this well, ghc has to be invoked with --show-packages with all
+      # package related flags the user has provided.
+      return 0
+      ;;
+    -e|-x|-hcsuf|-hisuf|-osuf|-framework)
+      # Do nothing. Next argument is not a flag.
+      return 0
+      ;;
+  esac
+
+  # Look at the current flag.
+  if [[ "$cur" == -* ]]; then
+    # All GHC flags start with a dash, so we want to see this before we start
+    # suggesting flags. Otherwise we would complete flags when the user might
+    # want to type a file name.
+    COMPREPLY=( $( compgen -W "$completions -x" -- "$cur" ) )
+  fi
+}
+
+complete -F _ghc -o default ghc
+complete -F _ghc -o default ghci