anchor.diff:  keywords = ( 'TRUE', 'True', 'true', 'FALSE', 'False', 'false',
                'namespace', 'enum', 'enumeration', 'Const', 'record', 'class', 'sequence',
                'Bool', 'Num', 'Real', 'String' )
  +debugging = 0 # causes exceptions to bypass IDL-file parser error handling
   
   class YYGlobals (object):
     def __init__ (self):
  
positive.code:     runtime.print_error (ex, isp._scanner)
    except AssertionError: raise
    except Exception, ex:
      # raise # pass exceptions on when debugging
      exstr = str (ex)
      if exstr: exstr = ': ' + exstr
      runtime.print_error (ParseError ('%s%s' % (ex.__class__.__name__, exstr)), isp._scanner)
  
negative.code:                                                 {{ else:               l = [ expression, "" ] }}
                                                  {{ l = [ IDENT ] + l + [ "" ] }}
            ) 
          ]                                       {{ return yy.nsadd_evalue (l[0], l[2], l[3], l[1]) }}
  rule enumeration_args:
          expression                              {{ l = [ expression ] }}
                                                  {{ if TS (expression): l = [ None ] + l }}
  