String .. String -- a sequence of consecutive strings

i1 : "a" .. "z"

o1 = (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x,
     ------------------------------------------------------------------------
     y, z)

o1 : Sequence

i2 : "aa" .. "ce"

o2 = (aa, ab, ac, ad, ae, ba, bb, bc, bd, be, ca, cb, cc, cd, ce)

o2 : Sequence

i3 : "aaa" .. "abc"

o3 = (aaa, aab, aac, aba, abb, abc)

o3 : Sequence

i4 : "佖" .. "佥"

o4 = (佖, 佗, 佘, 余, 佚, 佛, 作, 佝, 佞, 佟, 你, 佡, 佢, 佣, 佤, 佥)

o4 : Sequence