Run results for: SparseSet - object literal vs class

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/110.0

Browser: Firefox 110

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Object literal	36736.7 Ops/sec
Class	44303.6 Ops/sec

Script Preparation code:

var SparseSet1 = (input) => {
    const dense = input !== undefined ? new Array(input.length) : [];
    const sparse = [];

    const has = (value) => {
        return dense[sparse[value]] === value;
    };

    const add = (value) => {
        if (has(value)) return false;

        sparse[value] = dense.push(value) - 1;

        return true;
    };

    const remove = (value) => {
        if (!has(value)) return;

        const index = sparse[value];
        const swapped = dense.pop();
        if (swapped !== value) {
            dense[index] = swapped;
            sparse[swapped] = index;
        }
    };

    if (input !== undefined) {
        for (let i = 0; i < input.length; i++) {
            dense[i] = input[i];
            sparse[input[i]] = i;
        }
    }

    return {
        dense,
        sparse,
        has,
        add,
        remove,
    };
};

class SparseSet {
    constructor(input) {
        this.dense = input !== undefined ? new Array(input.length) : [];
        this.sparse = [];

        if (input !== undefined) {
            for (let i = 0; i < input.length; i++) {
                this.dense[i] = input[i];
                this.sparse[input[i]] = i;
            }
        }
    }

    has(value) {
        return this.dense[this.sparse[value]] === value;
    };

    add(value) {
        if (this.has(value)) return false;

        this.sparse[value] = this.dense.push(value) - 1;

        return true;
    };

    remove(value) {
        if (!this.has(value)) return;

        const index = this.sparse[value];
        const swapped = this.dense.pop();
        if (swapped !== value) {
            this.dense[index] = swapped;
            this.sparse[swapped] = index;
        }
    };
};
var SparseSet2 = SparseSet;

Tests:

Object literal
var set = SparseSet1([64, 11, 97, 1, 24, 25, 67, 100, 120, 130, 1001, 8, 2163]); for(let i = 1000; i < 1100; i++) { set.add(i); } for(let i = 0; i < 100; i++) { set.remove(i); }
Class
var set = new SparseSet2([64, 11, 97, 1, 24, 25, 67, 100, 120, 130, 1001, 8, 2163]); for(let i = 1000; i < 1100; i++) { set.add(i); } for(let i = 0; i < 100; i++) { set.remove(i); }

Run results for: SparseSet - object literal vs class

Object literal

Class