_all_matches`` = True.

NOTE: ``set_results_name`` returns a *copy* of the original :class:`ParserElement` object;
this is so that the client can define a basic element, such as an
integer, and reference it in multiple places with different names.

You can also set results names using the abbreviated syntax,
``expr("name")`` in place of ``expr.set_results_name("name")``
- see :class:`__call__`. If ``list_all_matches`` is required, use
``expr("name*")``.

Example::

    integer = Word(nums)
    date_str = (integer.set_results_name("year") + '/'
                + integer.set_results_name("month") + '/'
                + integer.set_results_name("day"))

    # equivalent form:
    date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
)