erevision
erevision is an alias for `ediff-revision' in `ediff.el
'.
(erevision &optional FILE STARTUP-HOOKS)
Run Ediff by comparing versions of a file.
The file is an optional FILE argument or the file entered at the prompt.
Default: the file visited by the current buffer.
Uses `vc.el' or `rcs.el' depending on `ediff-version-control-package'.