Here is a list of the completion commands defined in the minibuffer when completion is available.
SPC completes much like TAB, but never goes beyond the
next hyphen or space. If you have `auto-f' in the minibuffer and
type SPC, it finds that the completion is `auto-fill-mode',
but it stops completing after `fill-'. This gives
`auto-fill-'. Another SPC at this point completes all the
way to `auto-fill-mode'. SPC in the minibuffer when
completion is available runs the command
Here are some commands you can use to choose a completion from a window that displays a list of completions:
mouse-choose-completion). You normally use this command while point is in the minibuffer; but you must click in the list of completions, not in the minibuffer itself.
switch-to-completions). This paves the way for using the commands below. (Selecting that window in the usual ways has the same effect, but this way is more convenient.)
choose-completion). To use this command, you must first switch windows to the window that shows the list of completions.
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