1  module REXML
   2    class ParseException < RuntimeError
   3      attr_accessor :source, :parser, :continued_exception
   4 
   5      def initialize( message, source=nil, parser=nil, exception=nil )
   6        super(message)
   7        @source = source
   8        @parser = parser
   9        @continued_exception = exception
  10      end
  11 
  12      def to_s
  13        # Quote the original exception, if there was one
  14        if @continued_exception
  15          err = @continued_exception.inspect
  16          err << "\n"
  17          err << @continued_exception.backtrace.join("\n")
  18          err << "\n...\n"
  19        else
  20          err = ""
  21        end
  22 
  23        # Get the stack trace and error message
  24        err << super
  25 
  26        # Add contextual information
  27        if @source
  28          err << "\nLine: #{line}\n"
  29          err << "Position: #{position}\n"
  30          err << "Last 80 unconsumed characters:\n"
  31          err << @source.buffer[0..80].gsub(/\n/, ' ')
  32        end
  33        
  34        err
  35      end
  36 
  37      def position
  38        @source.current_line[0] if @source and defined? @source.current_line and
  39        @source.current_line
  40      end
  41 
  42      def line
  43        @source.current_line[2] if @source and defined? @source.current_line and 
  44        @source.current_line
  45      end
  46 
  47      def context
  48        @source.current_line
  49      end
  50    end  
  51  end