Peter (again), Something to think about until I get back to you tomorrow.
A set of flags Flag1, Flag2, . . . , Flag8 can be viewed as an array f(1) f(2) f(8) | | | | |bbbbbbbb|bbbbbbbb| . . . |bbbbbbbb| in each element of which the eight bit positions are labeled |b b b b b b b b| 1 2 3 4 5 6 7 8 If then 0 < i <= 8 is a byte subscript and 0 < j <= 8 is a bit subscript in some byte j can also be used to subscript an array of 8 masks mask(1), BL1'10000000' mask(2), BL1'01000000' mask(3), BL1'00100000' mask(4), BL1'00010000' mask(5), BL1'00001000' mask(6), BL1'00000100' mask(7), BL1'00000010' mask(8), BL1'00000001' usable to test any bit position in any byte-array element. If then having put flag names in ascending lexicographic sequence the position p of a flag name in this (also one-origin) sequence determines both i and j. We have i = floor[p/8] + 1 j = mod(p,8) + 1 The construction of a one-origin lexicographically ordered sequence of flag names is thus the only really interesting task here. John Gilmore, Ashland, MA 01721 - USA
