Swift Core Team going to hate you https://x.com/krzyzanowskim/status/1807853935064986109

StringHumanSubscript.swift

extension StringProtocol {
    
    /// str[NSRange(location:0, length: 9)]
    subscript(_ range: NSRange) -> SubSequence {
        guard let stringRange = Range<String.Index>(range, in: self) else {
            fatalError("String index is out of range")
        }
        return self[stringRange]
    }
    
    /// str[0]
    subscript(_ characterIndex: Int) -> Element? {
        self[self.index(startIndex, offsetBy: characterIndex)]
    }
    
    /// str[1..<3]
    subscript(_ range: Range<Int>) -> SubSequence {
        let start = self.index(startIndex, offsetBy: range.lowerBound)
        let end = self.index(start, offsetBy: range.upperBound - range.lowerBound)
        return self[start..<end]
    }
    
    /// str[1...3]
    subscript(_ range: ClosedRange<Int>) -> SubSequence {
        let start = self.index(startIndex, offsetBy: range.lowerBound)
        let end = self.index(start, offsetBy: range.upperBound - range.lowerBound)
        return self[start...end]
    }
    
}