def find_first_match(self, matcher, only_direct=False, include_self=True):
"""Finds the *first* node that matching callback returns true.
This will search not only this node but also any children nodes (in
depth first order, from right to left) and finally if nothing is
matched then ``None`` is returned instead of a node object.
:param matcher: callback that takes one positional argument (a node)
and returns true if it matches desired node or false
if not.
:param only_direct: only look at current node and its
direct children (implies that this does not
search using depth first).
:param include_self: include the current node during searching.
:returns: the node that matched (or ``None``)
"""
if only_direct:
if include_self:
it = itertools.chain([self], self.reverse_iter())
else:
it = self.reverse_iter()
else:
it = self.dfs_iter(include_self=include_self)
return iter_utils.find_first_match(it, matcher)
def find_first_match(self, matcher, only_direct=False, include_self=True):
"""Finds the *first* node that matching callback returns true.
This will search not only this node but also any children nodes (in
depth first order, from right to left) and finally if nothing is
matched then ``None`` is returned instead of a node object.
:param matcher: callback that takes one positional argument (a node)
and returns true if it matches desired node or false
if not.
:param only_direct: only look at current node and its
direct children (implies that this does not
search using depth first).
:param include_self: include the current node during searching.
:returns: the node that matched (or ``None``)
"""
if only_direct:
if include_self:
it = itertools.chain([self], self.reverse_iter())
else:
it = self.reverse_iter()
else:
it = self.dfs_iter(include_self=include_self)
return iter_utils.find_first_match(it, matcher)
def test_find_first_match_not_found(self):
it = iter(string.ascii_lowercase)
self.assertIsNone(iter_utils.find_first_match(it,
lambda v: v == ''))
def test_find_first_match(self):
it = forever_it()
self.assertEqual(100, iter_utils.find_first_match(it,
lambda v: v == 100))
def test_find_first_match_not_found(self):
it = iter(string.ascii_lowercase)
self.assertIsNone(iter_utils.find_first_match(it,
lambda v: v == ''))
def test_find_first_match(self):
it = forever_it()
self.assertEqual(100, iter_utils.find_first_match(it,
lambda v: v == 100))
