Usage of rest parameter with object - ecmascript-6

Question

I am trying to pull the user information by passing some object values as rest parameter. Whenever I try to pass 2 arguments, the code throws an error (undefined). What is it that I am missing?
Here is the Jsfiddle link of what I am trying to do.
let userAddress = [{
"street": "someStreet1",
"house": "1",
"person": "User1"
}, {
"street": "someStreet2",
"house": "2",
"person": "User2"
}, {
"street": "someStreet3",
"house": "3",
"person": "User3"
}];
let userInfo = [];
let addressToCheck = (...newUserHouse) => {
for (let address of userAddress) {
if (newUserHouse == address.house) {
userInfo.push(address.person);
console.log(userInfo);
}
}
}
console.log(addressToCheck(3, 2));
EDIT
Additional info:
I had this problem in which I had a JSON data and I had to pass multiple values and check whether those values were present in the dataset or not and if present, display the whole object.
For example; In the userAddress Array (as shown above) I need to check if 3, 2 (passed as an argument) are present as house number in userAddress. If they are present, then display the whole information about that particular object. As in this case, since 3, 2 are valid house numbers, the expected result should be:
Object { "street": "someStreet2", "house": "2", "person": "User2" }
Object { "street": "someStreet3", "house": "3", "person": "User3" }

Answer 1

The code does not throw an undefined error, it simply logs the value undefined. And that happens because you are calling console.log on the return value of addressToCheck but the function doesn't return a value, so it implicitly returns undefined. See console.log returns an additional undefined.
However, there are more problems with your code. It only accidentally works when you pass a single argument because you are using loose comparison (==).
The value of a rest parameter is always an array. That means you are really doing the following comparisons:
[1, 2] == "1"
[1, 2] == "2"
[1, 2] == "3"
I hope it's obvious why this cannot work. An array with multiple elements cannot be equal to a single "element", so the if condition is never fulfilled.
It works accidentally with a single argument because the string representation of [1] is simply "1". The string representation if [1,2] however is "1,2".
You are not explaining what the desired outcome is but if you want to select all addresses for the provided input, you should be using .filter instead. And you can convert the provided arguments to a set for fast lookup.
Instead of assigning values to an "external" array, simply return the result from the function.
let userAddress = [{
"street": "someStreet1",
"house": "1",
"person": "User1"
}, {
"street": "someStreet2",
"house": "2",
"person": "User2"
}, {
"street": "someStreet3",
"house": "3",
"person": "User3"
}];
let addressToCheck = (...newUserHouse) => {
newUserHouse = new Set(newUserHouse);
return userAddress.filter(address => newUserHouse.has(address.house));
};
console.log(addressToCheck("3", "2"));

Answer 2

A functional way to achieve this using ES6 is to utilize the Array's filter() and includes() methods in a custom function, (namely getUsersMatchingHouseNumbers), as shown in the gist below:
const userData = [{
"street": "someStreet1",
"house": 1,
"person": "User1"
}, {
"street": "someStreet2",
"house": 2,
"person": "User2"
}, {
"street": "someStreet3",
"house": 3,
"person": "User3"
}]
function getUsersMatchingHouseNumbers(userData, ...houseNumbers) {
return userData.filter(({ house }) => houseNumbers.includes(house));
}
console.log(getUsersMatchingHouseNumbers(userData, 1, 3));
Notes
The userData.filter(({ house }) part uses Object destructuring to obtain only the house property/value from each userData object.
The getUsersMatchingHouseNumbers function returns an array of user objects whose house number matches those passed to the function when it is invoked.

Answer 3

In my code, I was missing out the point that rest parameters are an array of parameters and in order to manipulate them, we have to iterate over them too.
let userAddress = [{
"street": "someStreet1",
"house": 1,
"person": "User1"
}, {
"street": "someStreet2",
"house": 2,
"person": "User2"
}, {
"street": "someStreet3",
"house": 3,
"person": "User3"
}]
let addressToCheck = (...houses) => {
for(let house of houses){
for (let user of userAddress) {
if(user.house === house){
console.log(user);
break;
}
}
}
}
console.log(addressToCheck(1, 3));