text: #
  # This source file is part of the EdgeDB open source project.
  #
  # Copyright 2016-present MagicStack Inc. and the EdgeDB authors.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  #
  
  
  import re
  
  from .parser.grammar import keywords
  
  
  _re_ident = re.compile(r'[^\W\d]\w*')
  
  
  def quote_literal(text):
      return "'" + text.replace("'", R"\'") + "'"
  
  
  def dollar_quote_literal(text):
      quote = '$$'
      qq = 0
  
      while quote in text:
          if qq % 16 < 10:
              qq += 10 - qq % 16
  
          quote = '${:x}$'.format(qq)[::-1]
          qq += 1
  
      return quote + text + quote
  
  
  def disambiguate_identifier(text):
      if (keywords.by_type[keywords.RESERVED_KEYWORD].get(text.lower()) or
              not _re_ident.fullmatch(text)):
          return '`{}`'.format(text)
      else:
          return text
  