2877     string toISOString() const @safe pure nothrow  in toISOString()  function
2883             toISOString(w);  in toISOString()
2890     void toISOString(W)(ref W writer) const
2894         _date.toISOString(writer);
2906         assert(DateTime(Date(2010, 7, 4), TimeOfDay(7, 6, 12)).toISOString() ==
2909         assert(DateTime(Date(1998, 12, 25), TimeOfDay(2, 15, 0)).toISOString() ==
2912         assert(DateTime(Date(0, 1, 5), TimeOfDay(23, 9, 59)).toISOString() ==
2915         assert(DateTime(Date(-4, 1, 5), TimeOfDay(0, 0, 2)).toISOString() ==
2922         assert(DateTime(Date(9, 12, 4), TimeOfDay(0, 0, 0)).toISOString() == "00091204T000000");
2923         assert(DateTime(Date(99, 12, 4), TimeOfDay(5, 6, 12)).toISOString() == "00991204T050612");
2924 …      assert(DateTime(Date(999, 12, 4), TimeOfDay(13, 44, 59)).toISOString() == "09991204T134459");
2925 …      assert(DateTime(Date(9999, 7, 4), TimeOfDay(23, 59, 59)).toISOString() == "99990704T235959");
2926 …    assert(DateTime(Date(10000, 10, 20), TimeOfDay(1, 1, 1)).toISOString() == "+100001020T010101");
2929         assert(DateTime(Date(0, 12, 4), TimeOfDay(0, 12, 4)).toISOString() == "00001204T001204");
2930         assert(DateTime(Date(-9, 12, 4), TimeOfDay(0, 0, 0)).toISOString() == "-00091204T000000");
2931         assert(DateTime(Date(-99, 12, 4), TimeOfDay(5, 6, 12)).toISOString() == "-00991204T050612");
2932 …    assert(DateTime(Date(-999, 12, 4), TimeOfDay(13, 44, 59)).toISOString() == "-09991204T134459");
2933 …    assert(DateTime(Date(-9999, 7, 4), TimeOfDay(23, 59, 59)).toISOString() == "-99990704T235959");
2934 …   assert(DateTime(Date(-10000, 10, 20), TimeOfDay(1, 1, 1)).toISOString() == "-100001020T010101");
2938         assert(cdt.toISOString() == "19990706T123033");
2939         assert(idt.toISOString() == "19990706T123033");
3108         cares about the format of the string should use `toISOString`,
3733     assert(dt.toISOString() == "20000611T103140");
7320     string toISOString() const @safe pure nothrow  in toISOString()  function
7326             toISOString(w);  in toISOString()
7335         assert(Date(2010, 7, 4).toISOString() == "20100704");
7336         assert(Date(1998, 12, 25).toISOString() == "19981225");
7337         assert(Date(0, 1, 5).toISOString() == "00000105");
7338         assert(Date(-4, 1, 5).toISOString() == "-00040105");
7344         assert(Date(9, 12, 4).toISOString() == "00091204");
7345         assert(Date(99, 12, 4).toISOString() == "00991204");
7346         assert(Date(999, 12, 4).toISOString() == "09991204");
7347         assert(Date(9999, 7, 4).toISOString() == "99990704");
7348         assert(Date(10000, 10, 20).toISOString() == "+100001020");
7351         assert(Date(0, 12, 4).toISOString() == "00001204");
7352         assert(Date(-9, 12, 4).toISOString() == "-00091204");
7353         assert(Date(-99, 12, 4).toISOString() == "-00991204");
7354         assert(Date(-999, 12, 4).toISOString() == "-09991204");
7355         assert(Date(-9999, 7, 4).toISOString() == "-99990704");
7356         assert(Date(-10000, 10, 20).toISOString() == "-100001020");
7360         assert(cdate.toISOString() == "19990706");
7361         assert(idate.toISOString() == "19990706");
7365     void toISOString(W)(ref W writer) const
7387         Date(2010, 7, 4).toISOString(w);
7390         Date(1998, 12, 25).toISOString(w);
7574         cares about the format of the string should use `toISOString`,
8296     assert(d.toISOString() == "20000611");
9051     string toISOString() const @safe pure nothrow  in toISOString()  function
9057             toISOString(w);  in toISOString()
9064     void toISOString(W)(ref W writer) const
9074         assert(TimeOfDay(0, 0, 0).toISOString() == "000000");
9075         assert(TimeOfDay(12, 30, 33).toISOString() == "123033");
9083         assert(tod.toISOString() == "123033");
9084         assert(ctod.toISOString() == "123033");
9085         assert(itod.toISOString() == "123033");
9148         cares about the format of the string should use `toISOString`,
9627     assert(t.toISOString() == "124140");