Fast(est) & consistent JavaScript BitSet (AKA bitvector, bitarray, bitstring) implementation. Implemented as part of my upcoming(...loading...) cell game engine, but perfectly usable as a standalone lib.

Features

• Fast!
• Fully tested
• Fully documented
• Both bitset & bitvector like methods
• Pascal methods respect immutability
• Chaining
• Lots of aliases
• Lots of output options
• ES6 binaries
• Made with bits of love!

Installation

npm

npm install cell-bitset

Usage

const bs1 = BitSet.create() // default length is 32
    .set(7)
    .set(54) // the length of the underlying bitvector is automatically resized to 55
    .set(23);

const bs2 = BitSet.create(68) // create a bitvector with a specific size
    .add(7, 67, 23);

const bs3 = new BitSet([7, 54, 23]); // use an iterable to initialize the bitset.

bs1.union(bs2);

expect(bs1.toString()).to.eql('{7, 23, 54, 67}');
expect(bs1.toString(2)).to.eql('10000000000001000000000000000000000000000000100000000000000010000000'); // will output the bitstring
expect(bs1.length).to.eql(68); // The length of the underlying bitvector. The length of bs1 is automatically resized
expect(bs1.cardinality).to.eql(4); // i.e. the number of flipped bits

const bs4 = bs3.Union(bs2); // use Pascal case Union to output a new bitset and leave bs3 unchanged

expect(bs3.toString()).to.eql('{7, 23, 54}');
expect(bs4.toString()).to.eql('{7, 23, 54, 67}');

For more usage example see the unit tests.