hamlet-mode is an Emacs major mode for editing files written in Hamlet, a Haskell compile-time HTML templating engine. Currently it only provides syntax highlighting.
If you have Emacs >= 24, you can conveniently install hamlet-mode via the package
in MELPA.
To install manually, simply put hamlet-mode.el wherever you want, load it, and (require 'hamlet-mode).
If you want to highlight quasiquoted Hamlet, install mmm-mode and do something like this:
(require 'mmm-vars)
(require 'mmm-auto)
(setq mmm-global-mode 'maybe)
(mmm-add-classes
'((hamlet-quasiquote
:submode hamlet-mode
:delimiter-mode nil
:front "\\[x?hamlet|"
:back "|\\]")))
(mmm-add-mode-ext-class 'haskell-mode nil 'hamlet-quasiquote)