def move_nodes(nodes, new_parent, in_place=True, remove_empty=True, remove_trivial_unary=True):
if not in_place:
nodes = pstree.clone_and_find(nodes + [new_parent])
new_parent = nodes[-1]
nodes = nodes[:-1]
# Find the insertion point in the new parent's subtrees
old_parent = nodes[0].parent
nodes.sort(key=lambda x: x.span)
node_span = (nodes[0].span[0], nodes[-1].span[1])
insertion_point = 0
if new_parent.subtrees[0].span[0] == node_span[1]:
# Inserting before all that are there currently
pass
elif new_parent.subtrees[0].span[0] == node_span[0]:
# Inserting before all that are there currently
pass
else:
for subtree in new_parent.subtrees:
if subtree.span[0] == node_span[1]:
break
insertion_point += 1
if subtree.span[1] == node_span[0]:
break
if insertion_point > len(new_parent.subtrees):
return (False, "new_parent did not have suitable insertion point")
# Move the nodes across
for node in nodes:
node.parent.subtrees.remove(node)
new_parent.subtrees.insert(insertion_point, node)
node.parent = new_parent
insertion_point += 1
# If the nodes left behind are empty, remove them
to_check_for_unary = old_parent
if remove_empty and len(old_parent.subtrees) == 0:
to_remove = old_parent
while len(to_remove.parent.subtrees) == 1:
to_remove = to_remove.parent
to_remove.parent.remove(to_remove)
# If the removal applies, then we will need to check at that level for
# unaries, rather than down at the old_parent
to_check_for_unary = to_remove.parent
# Remove trivial unaries
if remove_trivial_unary:
to_check = to_check_for_unary
if len(to_check.subtrees) == 1 and to_check.label == to_check.subtrees[0].label:
to_check.subtrees = to_check.subtrees[0].subtrees
for subtree in to_check.subtrees:
subtree.parent = to_check
new_parent.root().calculate_spans()
return (True, (new_parent.root(), nodes, new_parent))
def remove_node_by_node(node, in_place):
if not in_place:
node = pstree.clone_and_find(node)
parent = node.parent
position = parent.subtrees.index(node)
init_position = position
parent.subtrees.pop(position)
for subtree in node.subtrees:
subtree.parent = parent
parent.subtrees.insert(position, subtree)
position += 1
return (True, (parent, node, init_position, position))
def change_label_by_node(node, new_label, in_place):
if not in_place:
node = pstree.clone_and_find(node)
node.label = new_label
return (True, (node.root(), node))