Antlr4.Runtime.UnbufferedTokenStream.GetText C# (CSharp) Method

        public virtual string GetText(Interval interval)
        {
            int bufferStartIndex = GetBufferStartIndex();
            int bufferStopIndex = bufferStartIndex + tokens.Length - 1;
            int start = interval.a;
            int stop = interval.b;
            if (start < bufferStartIndex || stop > bufferStopIndex)
            {
                throw new NotSupportedException("interval " + interval + " not in token buffer window: " + bufferStartIndex + ".." + bufferStopIndex);
            }
            int a = start - bufferStartIndex;
            int b = stop - bufferStartIndex;
            StringBuilder buf = new StringBuilder();
            for (int i = a; i <= b; i++)
            {
                IToken t = tokens[i];
                buf.Append(t.Text);
            }
            return buf.ToString();
        }