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doc/todo/vicfg_comment_gotcha.mdwn

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+A user might run vicfg and want to reset a line back to the default value
+from the value they have periously set. A natural way to do that is to
+comment out the line (or delete it). However, what that actually does is
+vicfg parses the result and skips over that setting, since it's not
+present, and so no change is saved.
+
+It could try to parse commented out lines and detect deleted lines,
+but that way lies madness. Also, it's not at all clear what the "default"
+should be in response to such an action. The default varies per type of
+configuration, and vicfg does't know about defaults.
+
+Instead, I think it should detect when a setting provided in the input
+version of the file is not present in the output version, and plop the user
+back into the editor with an error, telling them that cannot be handled,
+and suggesting they instead change the value to the value they now want it
+to have.