forked from varia/varia.website
68 lines
1.7 KiB
Python
68 lines
1.7 KiB
Python
|
from __future__ import absolute_import, division, unicode_literals
|
||
|
|
from six import text_type
|
||
|
|
|
||
|
|
from bisect import bisect_left
|
||
|
|
|
||
|
|
from ._base import Trie as ABCTrie
|
||
|
|
|
||
|
|
|
||
|
|
class Trie(ABCTrie):
|
||
|
|
def __init__(self, data):
|
||
|
|
if not all(isinstance(x, text_type) for x in data.keys()):
|
||
|
|
raise TypeError("All keys must be strings")
|
||
|
|
|
||
|
|
self._data = data
|
||
|
|
self._keys = sorted(data.keys())
|
||
|
|
self._cachestr = ""
|
||
|
|
self._cachepoints = (0, len(data))
|
||
|
|
|
||
|
|
def __contains__(self, key):
|
||
|
|
return key in self._data
|
||
|
|
|
||
|
|
def __len__(self):
|
||
|
|
return len(self._data)
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
return iter(self._data)
|
||
|
|
|
||
|
|
def __getitem__(self, key):
|
||
|
|
return self._data[key]
|
||
|
|
|
||
|
|
def keys(self, prefix=None):
|
||
|
|
if prefix is None or prefix == "" or not self._keys:
|
||
|
|
return set(self._keys)
|
||
|
|
|
||
|
|
if prefix.startswith(self._cachestr):
|
||
|
|
lo, hi = self._cachepoints
|
||
|
|
start = i = bisect_left(self._keys, prefix, lo, hi)
|
||
|
|
else:
|
||
|
|
start = i = bisect_left(self._keys, prefix)
|
||
|
|
|
||
|
|
keys = set()
|
||
|
|
if start == len(self._keys):
|
||
|
|
return keys
|
||
|
|
|
||
|
|
while self._keys[i].startswith(prefix):
|
||
|
|
keys.add(self._keys[i])
|
||
|
|
i += 1
|
||
|
|
|
||
|
|
self._cachestr = prefix
|
||
|
|
self._cachepoints = (start, i)
|
||
|
|
|
||
|
|
return keys
|
||
|
|
|
||
|
|
def has_keys_with_prefix(self, prefix):
|
||
|
|
if prefix in self._data:
|
||
|
|
return True
|
||
|
|
|
||
|
|
if prefix.startswith(self._cachestr):
|
||
|
|
lo, hi = self._cachepoints
|
||
|
|
i = bisect_left(self._keys, prefix, lo, hi)
|
||
|
|
else:
|
||
|
|
i = bisect_left(self._keys, prefix)
|
||
|
|
|
||
|
|
if i == len(self._keys):
|
||
|
|
return False
|
||
|
|
|
||
|
|
return self._keys[i].startswith(prefix)
|