inc method
Increment all values by incrementAmount.
1, 2, 3.inc() returns 2, 3, 4.
1, 2, 3.inc(2) returns 3, 4, 5.
1, 2, 3.inc(-2) returns -1, 0, 1.
incrementAmount can be positive or negative.
Implementation
Set<N> inc([N? incrementAmount]) {
return h
.incrementIterable(
original: this,
increment: incrementAmount,
)
.toSet();
}