How to use "is" in predicates?

Question

IT terminology

isQueueOverWlow or queueIsOverFlow?
isQueueEmpty or queueIsEmpty?

And is there a single standard, as I assume?

Answer 1

There is no single standard, but it is often possible to abandon is altogether, and leave only:
queueOverflow
queueEmpty

Answer 2

is definitely shouldn't be in the middle. If it is needed by meaning, then only at the beginning.

Answer 3

isNone, isEmpty
Although, in Haskell you can use shorter
null