private String jsonString(PositionalBufferedStream in,int quote)
			throws IOException
			{
			StringBuilder b=new StringBuilder();
			int c;
			while(((c=in.read()))!=-1)
				{
				if(c=='\\')
					{
					switch(c=in.read())
						{
						case -1:throw new IOException("\\ followed by EOF");
						case 'n': b.append("\n"); break;
						case 't': b.append("\t"); break;
						case 'r': b.append("\r"); break;
						case '\'': b.append("\'"); break;
						case '\"': b.append("\""); break;
						default: b.append((char)c);break;
						}
					}
				else if(c==quote)
					{
					return b.toString();
					}
				else
					{
					b.append((char)c);
					}
				}
			
			throw new IOException("cannot parse string");
			}