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+This file provides `haskell-tab-indent-mode`, a simple Emacs
+indentation minor mode for Haskell projects which require tabs for
+indentation and do not permit spaces (except for where clauses, as a
+special case).  A prominent example of such a project is
+[git-annex][].
+
+The user may use TAB to cycle between possible indentations.
+
+# Installation
+
+You may copy `haskell-tab-indent.el` to somewhere in your `load-path`
+and simply
+
+    (autoload 'haskell-tab-indent-mode "haskell-tab-indent.el")
+
+Or you may use [git subtrees][]:
+
+    emacs-pkg-subtree pull https://git.spwhitton.name/haskell-tab-indent 0.1.0
+
+[git subtrees]: https://spwhitton.name/blog/entry/emacs-pkg-subtree/
+
+# Usage
+
+If you set `indent-tabs-mode` in the `.dir-locals.el` file for a
+project requiring tabs, you can use something like this in your init
+file to enable this mode for such projects, defaulting to the usual
+`haskell-indentation-mode`:
+
+    (add-hook 'haskell-mode-hook
+                (lambda ()
+                  (add-hook 'hack-local-variables-hook
+                            (lambda ()
+                              (if indent-tabs-mode
+                                  (haskell-tab-indent-mode)
+                                (haskell-indentation-mode)))
+                            nil t))) ; local hook
+
+[git-annex]: https://git-annex.branchable.com/coding_style/