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from typing import Iterator, Tuple, Union
from ...errors import Errors
from ...symbols import NOUN, PRON, PROPN
from ...tokens import Doc, Span
def noun_chunks(doclike: Union[Doc, Span]) -> Iterator[Tuple[int, int, int]]:
"""
Detect base noun phrases from a dependency parse for Haitian Creole.
Works on both Doc and Span objects.
"""
# Core nominal dependencies common in Haitian Creole
labels = [
"nsubj",
"obj",
"obl",
"nmod",
"appos",
"ROOT",
]
# Modifiers to optionally include in chunk (to the right)
post_modifiers = ["compound", "flat", "flat:name", "fixed"]
doc = doclike.doc
if not doc.has_annotation("DEP"):
raise ValueError(Errors.E029)
np_deps = {doc.vocab.strings.add(label) for label in labels}
np_mods = {doc.vocab.strings.add(mod) for mod in post_modifiers}
conj_label = doc.vocab.strings.add("conj")
np_label = doc.vocab.strings.add("NP")
adp_pos = doc.vocab.strings.add("ADP")
cc_pos = doc.vocab.strings.add("CCONJ")
prev_end = -1
for i, word in enumerate(doclike):
if word.pos not in (NOUN, PROPN, PRON):
continue
if word.left_edge.i <= prev_end:
continue
if word.dep in np_deps:
right_end = word
# expand to include known modifiers to the right
for child in word.rights:
if child.dep in np_mods:
right_end = child.right_edge
elif child.pos == NOUN:
right_end = child.right_edge
left_index = word.left_edge.i
# Skip prepositions at the start
if word.left_edge.pos == adp_pos:
left_index += 1
prev_end = right_end.i
yield left_index, right_end.i + 1, np_label
elif word.dep == conj_label:
head = word.head
while head.dep == conj_label and head.head.i < head.i:
head = head.head
if head.dep in np_deps:
left_index = word.left_edge.i
if word.left_edge.pos == cc_pos:
left_index += 1
prev_end = word.i
yield left_index, word.i + 1, np_label
SYNTAX_ITERATORS = {"noun_chunks": noun_chunks}