text: """
      pygments.lexers.rnc
      ~~~~~~~~~~~~~~~~~~~
  
      Lexer for Relax-NG Compact syntax
  
      :copyright: Copyright 2006-2022 by the Pygments team, see AUTHORS.
      :license: BSD, see LICENSE for details.
  """
  
  from pygments.lexer import RegexLexer
  from pygments.token import Text, Comment, Operator, Keyword, Name, String, \
      Punctuation
  
  __all__ = ['RNCCompactLexer']
  
  
  class RNCCompactLexer(RegexLexer):
      """
      For `RelaxNG-compact <http://relaxng.org>`_ syntax.
  
      .. versionadded:: 2.2
      """
  
      name = 'Relax-NG Compact'
      aliases = ['rng-compact', 'rnc']
      filenames = ['*.rnc']
  
      tokens = {
          'root': [
              (r'namespace\b', Keyword.Namespace),
              (r'(?:default|datatypes)\b', Keyword.Declaration),
              (r'##.*$', Comment.Preproc),
              (r'#.*$', Comment.Single),
              (r'"[^"]*"', String.Double),
              # TODO single quoted strings and escape sequences outside of
              # double-quoted strings
              (r'(?:element|attribute|mixed)\b', Keyword.Declaration, 'variable'),
              (r'(text\b|xsd:[^ ]+)', Keyword.Type, 'maybe_xsdattributes'),
              (r'[,?&*=|~]|>>', Operator),
              (r'[(){}]', Punctuation),
              (r'.', Text),
          ],
  
          # a variable has been declared using `element` or `attribute`
          'variable': [
              (r'[^{]+', Name.Variable),
              (r'\{', Punctuation, '#pop'),
          ],
  
          # after an xsd:<datatype> declaration there may be attributes
          'maybe_xsdattributes': [
              (r'\{', Punctuation, 'xsdattributes'),
              (r'\}', Punctuation, '#pop'),
              (r'.', Text),
          ],
  
          # attributes take the form { key1 = value1 key2 = value2 ... }
          'xsdattributes': [
              (r'[^ =}]', Name.Attribute),
              (r'=', Operator),
              (r'"[^"]*"', String.Double),
              (r'\}', Punctuation, '#pop'),
              (r'.', Text),
          ],
      }
  