Source code for colonel.emptynode

# Copyright 2018 The NLP Odyssey Authors.
# Copyright 2018 Marco Nicola <marconicola@disroot.org>
#
# 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.

"""Module providing the :class:`.EmptyNode` class."""

from typing import Optional
from colonel.base_rich_sentence_element import BaseRichSentenceElement

__all__ = ['EmptyNode']


[docs]class EmptyNode(BaseRichSentenceElement): """Representation of an *Empty Node* sentence element""" __slots__ = ('main_index', 'sub_index') def __init__( self, main_index: Optional[int] = None, sub_index: Optional[int] = None, **kwargs ) -> None: super(EmptyNode, self).__init__(**kwargs) #: The primary index of the empty node. #: #: This usually corresponds to the value of the :attr:`.Word.index` #: after which the empty node is inserted, or to zero (``0``) if the #: empty node is inserted before the first word of the sentence (the #: one with *index* equal to ``1``). #: #: It is compatible with *CoNLL-U* ``ID`` field, which in case of an #: empty node is a decimal number: the *main index* here corresponds #: to the integer part of such value. self.main_index: Optional[int] = main_index #: The secondary index of the empty node. #: #: It is compatible with *CoNLL-U* ``ID`` field, which in case of an #: empty node is a decimal number: the *sub index* here corresponds #: to the decimal part of such value. self.sub_index: Optional[int] = sub_index
[docs] def is_valid(self) -> bool: """Returns whether or not the object can be considered valid, however ignoring the context of the sentence in which the word itself is possibly inserted. In compliance with the *CoNLL-U* format, an instance of type :class:`.EmptyNode` is considered valid only when :attr:`main_index` is set to a value equal to or greater than zero (``0``) **and** :attr:`sub_index` is set to a value greater than zero (``0``). """ return super(EmptyNode, self).is_valid() and \ self.main_index is not None and self.main_index >= 0 and \ self.sub_index is not None and self.sub_index > 0
[docs] def to_conllu(self) -> str: """Returns a *CoNLL-U* formatted representation of the element. No validity check is performed on the attributes; values not compatible with *CoNLL-U* format could lead to an incorrect output value or raising of exceptions. """ return '\t'.join([ f'{self.main_index}.{self.sub_index}', self.form or '_', self.lemma or '_', self.upos.name if self.upos else '_', self.xpos or '_', self._feats_to_conllu(), '_', # Head '_', # DepRel self._deps_to_conllu(), self.misc or '_' ])