How do I get structural equality while using the HashSet ?

[janand1977]

I need to find if a class object with same values (toString method) already exists in the collection. This does not work in the HashSet but works in the ordered set. Am I missing something?

[ZLY201]

Try this:

function isOrderedSetEqual(st1: OrderedSet<unkonwn>, st2: OrderedSet<unkonwn>) {
    if (st1.size() !== st2.size()) {
        return false;
    }
    return Array.from(st1).toString() === Array.from(st2).toString();
}

[janand1977]

Iimport { HashSet } from "js-sdsl";

class Vehicle{
/**
*
*/
constructor(public name: string, public model: string, public owner: string) {

}

}

const testHashSet =() =>{
let tset = new HashSet();

let x = new Vehicle("Honda", "crv","anand");
let y = new Vehicle("nissan","versa","sown");
let z = new Vehicle("Honda", "crv","anand");

tset.insert(x);
tset.insert(y);


let it = tset.find(z);  // this should return a iterator since x and z have equal values... How do i achieve this ????
if (it.equals(tset.end())){
    tset.insert(z);
}else{
    console.log(it.pointer)
    console.log('already found');
}

console.log(tset.length);

}

testHashSet();

[ZLY201]

ah sorry i miss the question at the first time, i'm afraid the HashSet doesn't support this function now, to check if two elements is equal when using hash container you can do things like this:

class Vehicle {
    constructor(name, model, owner) {
        this.name = name;
        this.model = model;
        this.owner = owner;
    }
    // your hash function here, please ensure it returns a unique value for whole database
    toString() { return this.name + this.model + this.owner; }
}

const x = new Vehicle("Honda", "crv", "anand");
const y = new Vehicle("nissan", "versa", "sown");
const z = new Vehicle("Honda", "crv", "anand");

const mp = new HashMap();

mp.setElement(x.toString(), x);
mp.setElement(y.toString(), y);

// Then it works well

let it = mp.find(z.toString());
if (it.equals(mp.end())) {
    mp.setElement(z.toString(), z);
} else {
    console.log(it.pointer)
    console.log('already found');
}

console.log(mp.length);    // logs 2 because z is equals to x