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Rails-reverse-rename-column

08.25.2009
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        Emacs lisp macro for rails development to reverse the order of the columns in rename_column
Could use this approach to automatically rewrite most of the migration's "down"

(defun rails-reverse-rename-column ()
  "In a rails migration, from point to end of buffer, reverse the order of renamed columns"
  (interactive)
  (save-excursion
    (while (re-search-forward "rename_column *\"\\([^\"]*\\)\" *, *\"\\([^\"]*\\)\" *, *\"\\([^\"]*\\)\" *$" nil t)
       (replace-match "rename_column \"\\1\", \"\\3\", \"\\2\""))))