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+;;; +hungry-delete.el -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2022  Case Duckworth
+
+;;; Code:
+
+(require 'hungry-delete)
+
+(defmacro +hungry-delete-define-alternative (func hd-func &optional direction)
+  "Define a `hungry-delete' alternative for FUNC.
+If the adjacent characters in DIRECTION are one of
+`hungry-delete-chars-to-skip', call HD-FUNC.  Otherwise, call
+FUNC.
+
+If DIRECTION is a positive integer or `forward', look forward.
+If it's negative or `backward', look backward.  If it's absent,
+this macro will try to guess based on the names of FUNC and
+HD-FUNC.
+
+This macro creates a function taking a prefix argument that's
+passed to both of FUNC and HD-FUNC."
+  (let ((name (intern (format "%s|%s" func hd-func)))
+        (lookfn (cond
+                 ((or (and (string-match-p "forward" (symbol-name func))
+                           (string-match-p "forward" (symbol-name hd-func))
+                           (not direction))
+                      (and (integerp direction)
+                           (< 0 direction))
+                      (eq direction 'forward))
+                  'looking-at)
+                 ((or (and (string-match-p "backward" (symbol-name func))
+                           (string-match-p "backward" (symbol-name hd-func))
+                           (not direction))
+                   (and (integerp direction)
+                           (> 0 direction))
+                      (eq direction 'backward))
+                  'looking-back)
+                 (:else (error "Bad direction: %S" direction))))
+        (arg (gensym)))
+    `(defun ,name (,arg)
+       ,(concat (format "Do `%s' or `%s', depending on whitespace.\n"
+                        func hd-func)
+                (format "Pass prefix argument %s to the underlying functions.\n"
+                        (upcase (symbol-name arg)))
+                "This function was defined by `define-hungry-delete-alternative'.")
+       (interactive "*p")               ; This is brittle
+       (if (,lookfn (format "[%s]" hungry-delete-chars-to-skip))
+           (,hd-func (or ,arg 1))
+         (,func ,arg)))))
+
+(provide '+hungry-delete)
+;;; +hungry-delete.el ends here
+