A previously floated change proposed a patch for registering dialplan variables, warning/preventing assignment of variables whose names could conflict with internal Asterisk (all uppercase) variables if they were registered, and being able to show a list of variables for user convenience.
Some people were highly critical of the change in that revision, so the next step is likely to tame this down quite a bit to simply have XML documentation for any internal Asterisk dialplan variables which can then be listed in a "core show variables" command, forgoing the ability to prevent people from shooting themselves in the foot. Can't win 'em all.
Since very little of the patch will carry forward, a new patch should be written from scratch.
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