[分享] [新手向] 不修改 nlinum.el 的代码加入自定义 current-line 符号 如"->" 的功能

[ingtshan]

如题如图

起初发现 nlinum 的高亮是高亮行号，那应该有地方修改样式，翻了代码找了好久终于找到这个函数（大佬勿喷），然后拿出来自定义，就有了上面的效果。

和大伙分享这份简单的喜悦 。

[ingtshan]

代码

(leaf nlinum
  :hook ((org-mode-hook . nlinum-mode)
         (prog-mode-hook . nlinum-mode))
  :config
  (setq nlinum-highlight-current-line t)
  (defconst my-nlinum-format-function
    (lambda (line width)
      (let* ((is-current-line (= line nlinum--current-line))
             (str (format nlinum-format line)))
        ;; use -> as current line
        ;; or change to any symbol you like
        ;; here
        (and is-current-line (setq str "->"))
        (when (< (length str) width)
          ;; Left pad to try and right-align the line-numbers.
          (setq str (concat (make-string (- width (length str)) ?\ ) str)))
        (put-text-property 0 width 'face
                           (if (and nlinum-highlight-current-line
                                    is-current-line)
                               'nlinum-current-line
                             'linum)
                           str)
        str)))
  ;;take effect
  (setq nlinum-format-function my-nlinum-format-function))

效果是这样的

如果觉得突兀 还可以类似下面这样，使得 “->” 跟着 行的数字 一起变长

        ;; use -> as current line
        ;; or change to any symbol you like
        ;; here
        ;; (and is-current-line (setq str "->"))
        (when is-current-line
          (let* ((ms "->")
                 (es "-")
                 (el (- (length str) (length ms))))
            (while (> el 0)
              (setq ms (concat es ms))
              (setq el (1- el)))
            (setq str ms)))