Szathmáry László honlapja @ DEIK

See also std/intsets

This is different from the previous HashSet. First, in this you can only store integers. Second, it's similar to Java's BitSet.

When to use it? If you want to store a lot of integers in a set, and the set is dense, then it's a good choice. In this case, intsets is very fast and efficient.

However, if your set is sparse and there's a huge distance between the elements (e.g. {1, 750_000, 2_000_000}), then a HashSet[int] is a better choice.

Its API is similar to the other set implementations. The following things are exported from this module:

clear, union, missingOrExcl, isNil, incl, excl, items, ==, <=, =copy,
toPackedSet, assign, PackedSet, symmetricDifference, contains, len, $,
initPackedSet, <, *, -, excl, disjoint, difference, +, card, intersection,
incl, containsOrIncl

Example:

import std/intsets

var
a: IntSet
b = initIntSet()
c = [8, 6, 3, 2, 1, 0].toIntSet()

echo a # {}
echo b # {}
echo c # {8, 6, 3, 2, 1, 0}

a.incl(2)
a.incl(2)
a.incl(5)
a.incl(3)
a.incl(3)

echo a # {2, 5, 3}

for n in a: # we can iterate over the elements
echo n