text: # coding: utf-8
  
  from __future__ import absolute_import
  # This module contains abstractions for the input stream. You don't have to
  # looks further, there are no pretty code.
  #
  # We define two classes here.
  #
  #   Mark(source, line, column)
  # It's just a record and its only use is producing nice error messages.
  # Parser does not use it for any other purposes.
  #
  #   Reader(source, data)
  # Reader determines the encoding of `data` and converts it to unicode.
  # Reader provides the following methods and attributes:
  #   reader.peek(length=1) - return the next `length` characters
  #   reader.forward(length=1) - move the current position to `length`
  #      characters.
  #   reader.index - the number of the current character.
  #   reader.line, stream.column - the line and the column of the current
  #      character.
  
  import codecs
  import re
  
  from ruamel.yaml.error import YAMLError, FileMark, StringMark
  from ruamel.yaml.compat import text_type, binary_type, PY3
  
  if False:  # MYPY
      from typing import Any, Dict, Optional, List, Union, Text  # NOQA
      from ruamel.yaml.compat import StreamTextType  # NOQA
  
  __all__ = ['Reader', 'ReaderError']
  
  
  class ReaderError(YAMLError):
  
      def __init__(self, name, position, character, encoding, reason):
          # type: (Any, Any, Any, Any, Any) -> None
          self.name = name
          self.character = character
          self.position = position
          self.encoding = encoding
          self.reason = reason
  
      def __str__(self):
          # type: () -> str
          if isinstance(self.character, binary_type):
              return "'%s' codec can't decode byte #x%02x: %s\n"  \
                     "  in \"%s\", position %d"    \
                     % (self.encoding, ord(self.character), self.reason,
                        self.name, self.position)
          else:
              return "unacceptable character #x%04x: %s\n"    \
                     "  in \"%s\", position %d"    \
                     % (self.character, self.reason,
                        self.name, self.position)
  
  
  class Reader(object):
      # Reader:
      # - determines the data encoding and converts it to a unicode string,
      # - checks if characters are in allowed range,
      # - adds '\0' to the end.
  
      # Reader accepts
      #  - a `str` object (PY2) / a `bytes` object (PY3),
      #  - a `unicode` object (PY2) / a `str` object (PY3),
      #  - a file-like object with its `read` method returning `str`,
      #  - a file-like object with its `read` method returning `unicode`.
  
      # Yeah, it's ugly and slow.
  
      def __init__(self, stream, loader=None):
          # type: (StreamTextType, Any) -> None
          self.loader = loader
          if self.loader is not None:
              self.loader._reader = self
          self.name = None
          self.stream = None  # type: Any  # as .read is called
          self.stream_pointer = 0
          self.eof = True
          self.buffer = u''
          self.pointer = 0
          self.raw_buffer = None  # type: Any
          self.raw_decode = None
          self.encoding = None  # type: Union[None, Text]
          self.index = 0
          self.line = 0
          self.column = 0
          if isinstance(stream, text_type):
              self.name = "<unicode string>"
              self.check_printable(stream)
              self.buffer = stream+u'\0'
          elif isinstance(stream, binary_type):
              self.name = "<byte string>"
              self.raw_buffer = stream
              self.determine_encoding()
          else:
              self.stream = stream
              self.name = getattr(stream, 'name', "<file>")
              self.eof = False
              self.raw_buffer = None
              self.determine_encoding()
  
      def peek(self, index=0):
          # type: (int) -> Text
          try:
              return self.buffer[self.pointer+index]
          except IndexError:
              self.update(index+1)
              return self.buffer[self.pointer+index]
  
      def prefix(self, length=1):
          # type: (int) -> Any
          if self.pointer+length >= len(self.buffer):
              self.update(length)
          return self.buffer[self.pointer:self.pointer+length]
  
      def forward(self, length=1):
          # type: (int) -> None
          if self.pointer+length+1 >= len(self.buffer):
              self.update(length+1)
          while length != 0:
              ch = self.buffer[self.pointer]
              self.pointer += 1
              self.index += 1
              if ch in u'\n\x85\u2028\u2029'  \
                      or (ch == u'\r' and self.buffer[self.pointer] != u'\n'):
                  self.line += 1
                  self.column = 0
              elif ch != u'\uFEFF':
                  self.column += 1
              length -= 1
  
      def get_mark(self):
          # type: () -> Any
          if self.stream is None:
              return StringMark(self.name, self.index, self.line, self.column,
                                self.buffer, self.pointer)
          else:
              return FileMark(self.name, self.index, self.line, self.column)
  
      def determine_encoding(self):
          # type: () -> None
          while not self.eof and (self.raw_buffer is None or
                                  len(self.raw_buffer) < 2):
              self.update_raw()
          if isinstance(self.raw_buffer, binary_type):
              if self.raw_buffer.startswith(codecs.BOM_UTF16_LE):
                  self.raw_decode = codecs.utf_16_le_decode  # type: ignore
                  self.encoding = 'utf-16-le'
              elif self.raw_buffer.startswith(codecs.BOM_UTF16_BE):
                  self.raw_decode = codecs.utf_16_be_decode  # type: ignore
                  self.encoding = 'utf-16-be'
              else:
                  self.raw_decode = codecs.utf_8_decode  # type: ignore
                  self.encoding = 'utf-8'
          self.update(1)
  
      # 4 if 32 bit unicode supported, 2 e.g. on MacOS (issue 56)
      try:
          NON_PRINTABLE = re.compile(
              u'[^\x09\x0A\x0D\x20-\x7E\x85'
              u'\xA0-\uD7FF'
              u'\uE000-\uFFFD'
              u'\U00010000-\U0010FFFF'
              u']'
          )
          UNICODE_SIZE = 4
      except:
          NON_PRINTABLE = re.compile(
              u'[^\x09\x0A\x0D\x20-\x7E\x85'
              u'\xA0-\uD7FF'
              u'\uE000-\uFFFD'
              u']'
          )
          UNICODE_SIZE = 2
  
      def check_printable(self, data):
          # type: (Any) -> None
          match = self.NON_PRINTABLE.search(data)
          if bool(match):
              character = match.group()
              position = self.index+(len(self.buffer)-self.pointer)+match.start()
              raise ReaderError(self.name, position, ord(character),
                                'unicode', "special characters are not allowed")
  
      def update(self, length):
          # type: (int) -> None
          if self.raw_buffer is None:
              return
          self.buffer = self.buffer[self.pointer:]
          self.pointer = 0
          while len(self.buffer) < length:
              if not self.eof:
                  self.update_raw()
              if self.raw_decode is not None:
                  try:
                      data, converted = self.raw_decode(self.raw_buffer,
                                                        'strict', self.eof)
                  except UnicodeDecodeError as exc:
                      if PY3:
                          character = self.raw_buffer[exc.start]
                      else:
                          character = exc.object[exc.start]
                      if self.stream is not None:
                          position = self.stream_pointer - \
                              len(self.raw_buffer) + exc.start
                      elif self.stream is not None:
                          position = self.stream_pointer - \
                              len(self.raw_buffer) + exc.start
                      else:
                          position = exc.start
                      raise ReaderError(self.name, position, character,
                                        exc.encoding, exc.reason)
              else:
                  data = self.raw_buffer
                  converted = len(data)
              self.check_printable(data)
              self.buffer += data
              self.raw_buffer = self.raw_buffer[converted:]
              if self.eof:
                  self.buffer += u'\0'
                  self.raw_buffer = None
                  break
  
      def update_raw(self, size=None):
          # type: (int) -> None
          if size is None:
              size = 4096 if PY3 else 1024
          data = self.stream.read(size)
          if self.raw_buffer is None:
              self.raw_buffer = data
          else:
              self.raw_buffer += data
          self.stream_pointer += len(data)
          if not data:
              self.eof = True
  
  # try:
  #     import psyco
  #     psyco.bind(Reader)
  # except ImportError:
  #     pass
  