systemf.el

(defvar systemf-mode-syntax-table nil "Syntax table for systemf mode.")

(setq systemf-mode-syntax-table
      (let ((syn-table (make-syntax-table)))
        (modify-syntax-entry ?\/ ". 14" syn-table)
        (modify-syntax-entry ?*  ". 23" syn-table)
        syn-table))

(defface systemf-lock-governing-face
  '((t (:foreground "black" :weight bold)))
  "Face for governing keywords.")
(defvar systemf-lock-governing-face 'systemf-lock-governing-face)

(defface systemf-lock-operator-face
  '((t (:foreground "brown")))
  "Face for operators.")
(defvar systemf-lock-operator-face 'systemf-lock-operator-face)

(setq systemf-governing '("let" "in" "as" "Some" "All"))
(setq systemf-operators '("=" "->" ":" "(" ")" "{" "}" ";"))
(setq systemf-keywords '("lambda" "if" "then" "else" "fix"))
(setq systemf-types '("Nat" "Bool" "Unit"))
(setq systemf-constants '("false" "true"))

(setq systemf-governing-regexp (regexp-opt systemf-governing 'words))
(setq systemf-operators-regexp (regexp-opt systemf-operators))
(setq systemf-keywords-regexp (regexp-opt systemf-keywords 'words))
(setq systemf-types-regexp (regexp-opt systemf-types 'words))
(setq systemf-constants-regexp (regexp-opt systemf-constants 'words))

(setq systemf-font-lock-keywords
      `((,systemf-governing-regexp . systemf-lock-governing-face)
        (,systemf-operators-regexp . systemf-lock-operator-face)
        (,systemf-keywords-regexp . font-lock-keyword-face)
        (,systemf-types-regexp . font-lock-type-face)
        (,systemf-constants-regexp . font-lock-constant-face)))

(define-derived-mode systemf-mode fundamental-mode "systemf"
  "major mode for editing systemf language (implemented in TaPL) code."
  (setq font-lock-defaults '((systemf-font-lock-keywords)))

  (setq-local comment-start "/*")
  (setq-local comment-end "*/"))