bug#33168: 26; Doc string of `region-bounds'

[Drew Adams <drew.adams@oracle.com>]

Doc string:

  Return the boundaries of the region as a pair of positions.
  Value is a list of cons cells of the form (START . END).

Those two sentences are incompatible.

The first says that it returns a _single pair_ of positions: (START END)
or (START . END).  (It doesn't say what it means by "pair".  If it means
a cons then it should say so.)

The second says that it returns a _list of such pairs_, that is, a list
of conses of the form (START . END), where START and END are buffer
positions.

Further, assuming that the second sentence is correct, something needs
to be said about what it means to be a boundary of the region.
Presumably, in the case of a contiguous region the return value is
((BEG . END)), where BEG is the start of the region and END is the END.
But what if the region is noncontiguous?  Something should be said
about what each (BEG<N> . END<N>) pair corresponds to (means).


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 of 2018-05-30
Repository revision: 07f8f9bc5a51f5aa94eb099f3e15fbe0c20ea1ea
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