Class IOStream

IPython/utils/io.py:22–84

@undoc
class IOStream:

    def __init__(self, stream, fallback=None):
        warn('IOStream is deprecated since IPython 5.0, use sys.{stdin,stdout,stderr} instead',
             DeprecationWarning, stacklevel=2)
        if not hasattr(stream,'write') or not hasattr(stream,'flush'):
            if fallback is not None:
                stream = fallback
            else:
                raise ValueError("fallback required, but not specified")
        self.stream = stream
        self._swrite = stream.write

        # clone all methods not overridden:
        def clone(meth):
            return not hasattr(self, meth) and not meth.startswith('_')
        for meth in filter(clone, dir(stream)):
            try:
                val = getattr(stream, meth)
            except AttributeError:
                pass
            else:
                setattr(self, meth, val)

    def __repr__(self):
        cls = self.__class__
        tpl = '{mod}.{cls}({args})'
        return tpl.format(mod=cls.__module__, cls=cls.__name__, args=self.stream)

    def write(self,data):
        warn('IOStream is deprecated since IPython 5.0, use sys.{stdin,stdout,stderr} instead',
             DeprecationWarning, stacklevel=2)
        try:
            self._swrite(data)
        except:
            try:
                # print handles some unicode issues which may trip a plain
                # write() call.  Emulate write() by using an empty end
                # argument.
                print(data, end='', file=self.stream)
            except:
                # if we get here, something is seriously broken.
                print('ERROR - failed to write data to stream:', self.stream,
                      file=sys.stderr)

    def writelines(self, lines):
        warn('IOStream is deprecated since IPython 5.0, use sys.{stdin,stdout,stderr} instead',
             DeprecationWarning, stacklevel=2)
        if isinstance(lines, str):
            lines = [lines]
        for line in lines:
            self.write(line)

    # This class used to have a writeln method, but regular files and streams
    # in Python don't have this method. We need to keep this completely
    # compatible so we removed it.

    @property