When I have to pass a predicate to a function, such as
filter and I want the negative of the predicate, sometimes the function includes a cousin such as
filterNot, but if it doesn’t, I’d like to complement the predicate. it is of course easy enough just to inline the complementation such as
data.filter(p => !predicate(p)), but it seems to me there should already be such a function. I searched for
predicate.complement but didn’t find such.
Does it already exist in the standard library?
I’m not sure how I’d write it myself in the general case.