Binary operator '==' cannot be applied to two operands

Question

I have a class with the protocol Equatable. The class looks like this:

class Item: Equatable {

    let item: [[Modifications: String]]

    init(it         


        

Answer 1

In your == function for Item objects, you need to specify further how to compare two types of arrays of dictionaries (specifically, two types of [[Modifications: String]]).

The following working solution compares your item arrays element by element (dictionary by dictionary), and == returns true only if the arrays contain the same number of dictionaries, and if all entries are alike and ordered the same fashion in the array of dictionares

func ==(lhs: Item, rhs: Item) -> Bool {

    if lhs.item.count == rhs.item.count {
        for (i, lhsDict) in lhs.item.enumerate() {
            if lhsDict != rhs.item[i] {
                return false
            }
        }
        return true
    }
    else {
        return false
    }
}

class Item : Equatable {

    let item: [[Modifications: String]]

    init(item: [[Modifications: String]]) {
        self.item = item
    }
}

You probably want to modify this into the form you actually want to use for comparison, but I hope you get the gist of it.

Note also that, if testing this in a playground, it's important that your == function definition func ==(lhs: Item, rhs: Item) -> Bool { .. should precede your class definition, otherwise you will get an error of nonconformance to Equatable.