slices.swift

extension String {
    /// Returns an array of substrings based on the provided ranges
    /// - Parameter ranges: Array of ranges to slice the string
    /// - Returns: Array of sliced strings
    func sliced(_ ranges: [Range<Int>]) -> [String] {
        ranges.map { range in
            let startIndex = self.index(self.startIndex, offsetBy: range.lowerBound)
            let endIndex = self.index(self.startIndex, offsetBy: range.upperBound)
            return String(self[startIndex..<endIndex])
        }
    }
    
    /// Returns an array of substrings based on the provided ranges with safe bounds
    /// - Parameter ranges: Array of ranges to slice the string
    /// - Returns: Array of safely sliced strings
    func safeSliced(_ ranges: [Range<Int>]) -> [String] {
        ranges.map { range in
            let safeLowerBound = max(0, range.lowerBound)
            let safeUpperBound = min(self.count, range.upperBound)
            
            guard safeLowerBound < self.count, safeUpperBound > 0, safeLowerBound < safeUpperBound else {
                return ""
            }
            
            let startIndex = self.index(self.startIndex, offsetBy: safeLowerBound)
            let endIndex = self.index(self.startIndex, offsetBy: safeUpperBound)
            return String(self[startIndex..<endIndex])
        }
    }
}

// Example usage:
let text = "Hello, World!"
let ranges = [0..<5, 7..<12]
let sliced = text.sliced(ranges)  // ["Hello", "World"]

let unsafeRanges = [-2..<5, 7..<20]
let safeSliced = text.safeSliced(unsafeRanges)  // ["Hello", "World!"]