That doesn't seem to be an array at all, if the idea is to check whether a number is within a range. Seems like an interesting data type though, a combination of a range data type and a map/associative array.
I was thinking of a sparse array but any name will do. obj[~42] ?
One may have a bunch of key ranges each associated with a value or one may have a key that should be "rounded" to the nearest key or retreave the one below or above it.
It feels like something basic enough to have in a language and I found it oddly complicated to write myself. Comparing it with all values doesn't seem like a very good solution.
