Can anyone explain the error message?

Using Swift
,
1

I understand that (in this code) I cannot compare generics that differ in types, but I do not understand the error message. Can anyone explain why it says it cannot compare "two 'Struct<String>' operands" when one is a String and other is an Int? I would expect the error message to be something like this

Error message that is intuitive to me (with my current understanding)

error: binary operator '==' cannot be applied to 'Struct<String>' and 'Struct<Int>' operands

Actual error message

error: binary operator '==' cannot be applied to two 'Struct<String>' operands

Code

struct Struct<T: Equatable> {
    let val: T

    init(_ val: T) {
        self.val = val
    }

    static func == (lhs: Struct, rhs: Struct) -> Bool{
        lhs.val == rhs.val
    }
}

print(Struct(0) == Struct(0))  // true
// print(Struct("0") == Struct(0))  // error: binary operator '==' cannot be applied to two 'Struct<String>' operands
2

Sounds like a compiler bug to me, not a deliberate message. Worth filing!

1 Like
4

Thank you for replying @jrose, I have created an issue.

PS: deleted the earlier message as I replied to my own question instead of yours :upside_down_face: apologies for the double pings.

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