I often find code that checks for out of range values, as in:
if (x < 5 or x > 6) {
// do stuff...
}
I like to rearrange it to get a slightly better visual cue:
if (x < 5 or 6 < x) {
// do stuff...
}
My question is whether there is mathematical notation for that. I'm no mathematician; I know about inequality/comparison operators and interval notation for closed and open-ended (between) ranges, but I have yet to stumble upon a good, concise representation for out-of-range.
I'm left with writing the inequalities, or the rather clumsy "all except" interval notation (−∞,5) ∪ (6,∞), So let's say I propose something in the lines of
<a,b<
as new interval notation; how would I go about getting it accepted?