pub fn partition<'a, A: 'a, I, F>(iter: I, pred: F) -> usize where
I: IntoIterator<Item = &'a mut A>,
I::IntoIter: DoubleEndedIterator,
F: FnMut(&A) -> bool, Expand description
Partition a sequence using predicate pred so that elements
that map to true are placed before elements which map to false.
The order within the partitions is arbitrary.
Return the index of the split point.
use itertools::partition;
let mut data = [7, 1, 1, 7, 1, 1, 7];
let split_index = partition(&mut data, |elt| *elt >= 3);
assert_eq!(data, [7, 7, 7, 1, 1, 1, 1]);
assert_eq!(split_index, 3);