relates to:

• SR-4660 Methods on self should not block unambiguous calls to free functions
• SR-8524 Shadowing in protocols leads to difficult to find bugs

Issue Description:

https://gist.github.com/krzyzanowskim/a373a7d68e6808c06d6760d2a834f488

String already have hasPefix() in stdlib

public func hasPrefix(_ prefix: String) -> Bool

so I will implement identical method in my public exception:

public extension String {
    // wait wait wait... why no error here?
    public func hasPrefix(_ prefix: String) -> Bool {
        return true // fake it till you make it
    }
}

and use it. This will execute my version of String.hasPrefix(), that is rather unexpected and error prone.

let s = "abcd"
if s.hasPrefix("oooo") {
    print("hasPrefix true")
}

¯_(ツ)_/¯