diff options
Diffstat (limited to 'misc/emacs')
| -rw-r--r-- | misc/emacs/nix-mode.el | 86 |
1 files changed, 84 insertions, 2 deletions
diff --git a/misc/emacs/nix-mode.el b/misc/emacs/nix-mode.el index 10035e96ef30..e129e9efe1d4 100644 --- a/misc/emacs/nix-mode.el +++ b/misc/emacs/nix-mode.el @@ -8,6 +8,20 @@ ;;; Code: +(defun nix-syntax-match-antiquote (limit) + (let ((pos (next-single-char-property-change (point) 'nix-syntax-antiquote + nil limit))) + (when (and pos (> pos (point))) + (goto-char pos) + (let ((char (char-after pos))) + (pcase char + (`?$ + (forward-char 2)) + (`?} + (forward-char 1))) + (set-match-data (list pos (point))) + t)))) + (defconst nix-font-lock-keywords '("\\_<if\\_>" "\\_<then\\_>" "\\_<else\\_>" "\\_<assert\\_>" "\\_<with\\_>" "\\_<let\\_>" "\\_<in\\_>" "\\_<rec\\_>" "\\_<inherit\\_>" "\\_<or\\_>" @@ -26,7 +40,8 @@ ("<[a-zA-Z0-9._\\+-]+\\(/[a-zA-Z0-9._\\+-]+\\)*>" . font-lock-constant-face) ("[a-zA-Z0-9._\\+-]*\\(/[a-zA-Z0-9._\\+-]+\\)+" - . font-lock-constant-face)) + . font-lock-constant-face) + (nix-syntax-match-antiquote 0 font-lock-preprocessor-face t)) "Font lock keywords for nix.") (defvar nix-mode-syntax-table @@ -38,6 +53,67 @@ table) "Syntax table for Nix mode.") +(defun nix-syntax-propertize-escaped-antiquote () + "Set syntax properies for escaped antiquote marks." + nil) + +(defun nix-syntax-propertize-multiline-string () + "Set syntax properies for multiline string delimiters." + (let* ((start (match-beginning 0)) + (end (match-end 0)) + (context (save-excursion (save-match-data (syntax-ppss start)))) + (string-type (nth 3 context))) + (pcase string-type + (`t + ;; inside a multiline string + ;; ending multi-line string delimiter + (put-text-property (1- end) end + 'syntax-table (string-to-syntax "|"))) + (`nil + ;; beginning multi-line string delimiter + (put-text-property start (1+ start) + 'syntax-table (string-to-syntax "|")))))) + +(defun nix-syntax-propertize-antiquote () + "Set syntax properties for antiquote marks." + (let* ((start (match-beginning 0))) + (put-text-property start (1+ start) + 'syntax-table (string-to-syntax "|")) + (put-text-property start (+ start 2) + 'nix-syntax-antiquote t))) + +(defun nix-syntax-propertize-close-brace () + "Set syntax properties for close braces. +If a close brace `}' ends an antiquote, the next character begins a string." + (let* ((start (match-beginning 0)) + (end (match-end 0)) + (context (save-excursion (save-match-data (syntax-ppss start)))) + (open (nth 1 context))) + (when open ;; a corresponding open-brace was found + (let* ((antiquote (get-text-property open 'nix-syntax-antiquote))) + (when antiquote + (put-text-property (+ start 1) (+ start 2) + 'syntax-table (string-to-syntax "|")) + (put-text-property start (1+ start) + 'nix-syntax-antiquote t)))))) + +(defun nix-syntax-propertize (start end) + "Special syntax properties for Nix." + ;; search for multi-line string delimiters + (goto-char start) + (remove-text-properties start end '(syntax-table nil nix-syntax-antiquote nil)) + (funcall + (syntax-propertize-rules + ("''\\${" + (0 (ignore (nix-syntax-propertize-escaped-antiquote)))) + ("''" + (0 (ignore (nix-syntax-propertize-multiline-string)))) + ("\\${" + (0 (ignore (nix-syntax-propertize-antiquote)))) + ("}" + (0 (ignore (nix-syntax-propertize-close-brace))))) + start end)) + (defun nix-indent-line () "Indent current line in a Nix expression." (interactive) @@ -69,7 +145,13 @@ The hook `nix-mode-hook' is run when Nix mode is started. (set-syntax-table nix-mode-syntax-table) ;; Font lock support. - (setq font-lock-defaults '(nix-font-lock-keywords nil nil nil nil)) + (setq-local font-lock-defaults '(nix-font-lock-keywords nil nil nil nil)) + + ;; Special syntax properties for Nix + (setq-local syntax-propertize-function 'nix-syntax-propertize) + + ;; Look at text properties when parsing + (setq-local parse-sexp-lookup-properties t) ;; Automatic indentation [C-j]. (set (make-local-variable 'indent-line-function) 'nix-indent-line) |