Source code for anytree.iterators.levelorderiter

from .abstractiter import AbstractIter


[docs]class LevelOrderIter(AbstractIter): """ Iterate over tree applying level-order strategy starting at `node`. >>> from anytree import Node, RenderTree, AsciiStyle, LevelOrderIter >>> f = Node("f") >>> b = Node("b", parent=f) >>> a = Node("a", parent=b) >>> d = Node("d", parent=b) >>> c = Node("c", parent=d) >>> e = Node("e", parent=d) >>> g = Node("g", parent=f) >>> i = Node("i", parent=g) >>> h = Node("h", parent=i) >>> print(RenderTree(f, style=AsciiStyle()).by_attr()) f |-- b | |-- a | +-- d | |-- c | +-- e +-- g +-- i +-- h >>> [node.name for node in LevelOrderIter(f)] ['f', 'b', 'g', 'a', 'd', 'i', 'c', 'e', 'h'] >>> [node.name for node in LevelOrderIter(f, maxlevel=3)] ['f', 'b', 'g', 'a', 'd', 'i'] >>> [node.name for node in LevelOrderIter(f, filter_=lambda n: n.name not in ('e', 'g'))] ['f', 'b', 'a', 'd', 'i', 'c', 'h'] >>> [node.name for node in LevelOrderIter(f, stop=lambda n: n.name == 'd')] ['f', 'b', 'g', 'a', 'i', 'h'] """ @staticmethod def _iter(children, filter_, stop, maxlevel): level = 1 while children: next_children = [] level += 1 if AbstractIter._abort_at_level(level, maxlevel): for child in children: if filter_(child): yield child else: for child in children: if filter_(child): yield child next_children += AbstractIter._get_children(child.children, stop) children = next_children