Returns %TRUE if @tag is toggled on at exactly this point. If @tag
is %NULL, returns %TRUE if any tag is toggled on at this point.
Note that if gtk_text_iter_starts_tag() returns %TRUE, it means that @iter is
at the beginning of the tagged range, and that the
character at @iter is inside the tagged range. In other
words, unlike gtk_text_iter_ends_tag(), if gtk_text_iter_starts_tag() returns
%TRUE, gtk_text_iter_has_tag() will also return %TRUE for the same
parameters.
Returns %TRUE if @tag is toggled on at exactly this point. If @tag is %NULL, returns %TRUE if any tag is toggled on at this point.
Note that if gtk_text_iter_starts_tag() returns %TRUE, it means that @iter is at the beginning of the tagged range, and that the character at @iter is inside the tagged range. In other words, unlike gtk_text_iter_ends_tag(), if gtk_text_iter_starts_tag() returns %TRUE, gtk_text_iter_has_tag() will also return %TRUE for the same parameters.