Newmoon.SchemeString.this C# (CSharp) Метод

        public char this[int index]
        {
            get { return isNative() ? _string[index] : _chars[index]; }
            set {
            ensureArray();
            if (!_mutable)
            throw new InvalidOperationException("Attempt to string-set! "+
                            "immutable string: "+this+" "+index);
            _chars[index] = value;
            }
        }