def set_binding_file_pointers(context)
      caller.each do |c|
        file, line = c.sub(/:in .*$/,'').split(':', 2)
        next if File.expand_path(file).match(/^#{Regexp.quote(IRT.lib_path)}/) # exclude irt internal callers
        context.binding_file = file
        context.binding_line_no = line
        break
      end
    end
def set_binding_file_pointers(context)
      caller.each do |c|
        file, line = c.sub(/:in .*$/,'').split(':', 2)
        next if File.expand_path(file).match(/^#{Regexp.quote(IRT.lib_path)}/) # exclude irt internal callers
        context.binding_file = file
        context.binding_line_no = line
        break
      end
    end
used for open the last file for editing