 
 internal extension Data {
     
+    @usableFromInline
     func subdataNoCopy(in range: Range<Int>) -> Data {
         
         // stored in heap, can reuse buffer

    /// Size of the inline buffer for `Foundation.Data` used in Swift 5.
    ///
    /// Used to determine wheather data is stored on stack or in heap.
    static var inlineBufferSize: Int {
        
        // Keep up to date

        }
    }
    
    @usableFromInline
    func suffixNoCopy(from index: Int) -> Data {
        return subdataNoCopy(in: index ..< count)
    }
    
    @usableFromInline
    func suffixCheckingBounds(from start: Int) -> Data {
        
        if count > start {
