etags-update: update TAGS when saving a file
Here comes another Emacs post!
I've pushed etags-update to github. It's a global minor mode that updates your TAGS when you save a file. See the README for details.
While we're on the subject of TAGS, I recommend etags-select.el which will show a menu of matching tags when you run etags-select-find-tag (which I've bound to M-.). Very handy.
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