4.4BSD/usr/src/contrib/emacs-18.57/lisp/tabify.elc

(defun untabify (start end) "\
Convert all tabs in region to multiple spaces, preserving columns.
The variable tab-width controls the action." (interactive "r") (byte-code "ˆŠŒÆ	\"ˆbˆÇÈÂÃ#…*`iÂÉÈ!ˆÊ`\"ˆj+ˆ‚))‡" [start end nil t column indent-tabs-mode narrow-to-region search-forward "	" skip-chars-backward delete-region] 7))

(defun tabify (start end) "\
Convert multiple spaces in region to tabs when possible.
A group of spaces is partially replaced by tabs
when this can be done without changing the column they end at.
The variable tab-width controls the action." (interactive "r") (byte-code "ˆŠŒÆ	\"ˆbˆÇÈÂÃ#…&iÃÉÊË!`\"ˆj*ˆ‚))‡" [start end nil t column indent-tabs-mode narrow-to-region re-search-forward "[ 	][ 	][ 	]*" delete-region match-beginning 0] 7))