Native coref component

licenses/3rd_party_licenses.txt

@@ -127,3 +127,36 @@ 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.
+
+
+coval
+-----
+
+* Files: scorer.py
+
+The implementations of ClusterEvaluator, lea, get_cluster_info, and
+get_markable_assignments are adapted from coval, which is distributed
+under the following license:
+
+The MIT License (MIT)
+
+Copyright 2018 Nafise Sadat Moosavi (ns.moosavi at gmail dot com)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+

spacy/errors.py

@@ -939,6 +939,7 @@ class Errors(metaclass=ErrorsWithCodes):
              "`{arg2}`={arg2_values} but these arguments are conflicting.")
     E1043 = ("Expected None or a value in range [{range_start}, {range_end}] for entity linker threshold, but got "
              "{value}.")
+    E1044 = ("Misalignment in coref. Head token has no match in training doc.")
 
 
 # Deprecated model shortcuts, only used in errors and warnings

spacy/ml/models/__init__.py

@@ -5,3 +5,10 @@
 from .tagger import *  # noqa
 from .textcat import *  # noqa
 from .tok2vec import *  # noqa
+
+# some models require Torch
+from thinc.util import has_torch
+if has_torch:
+    from .coref import * #noqa
+    from .span_predictor import * #noqa
+