>They look good - which is important. The trouble (for me) is that I
>want the notation for a new programming language and already use these
>characters. I have underscore as an optional separator for groups of
>digits - 123000 and 123_000 mean the same. The semicolon terminates a
>statement. Based on your second idea, though, maybe a colon could be
>used instead as in
XPL uses "(2)1011" for base 4,
"(3)03212" for octal,
"(4)0741" for base 16.
PL/I uses 8FXN for numeric hex and X suffix for a hex character constant.