namespace System.Buffers { public static class BuffersExtensions { public static SequencePosition? PositionOf<T>(ref ReadOnlySequence<T> source, T value) where T : IEquatable<T>; public static void CopyTo<T>(ref ReadOnlySequence<T> source, Span<T> destination); public static T[] ToArray<T>(ref ReadOnlySequence<T> sequence); public static void Write<T>(this IBufferWriter<T> writer, ReadOnlySpan<T> value); } }