wordtrie 0.0.3

WordTrie: a simple trie (prefix tree) for word and phrase matching

WordTrie

Example

Create a new trie:

from wordtrie import WordTrie
trie = WordTrie()

Words and their values are added to the trie with the add() method:

trie.add("She", 1)
trie.add("sea", 2)

Exact matches in the trie are found with the match() method:

print(trie.match("She"))
# 1
print(trie.match("sells"))
# None
print(trie.match("She sells"))
# None

All matches in a stream of words can be found with the search() method:

print(trie.search("She sells sea shells by the sea shore."))
# [1, 2, 2]

Phrases can be added too and will be split into a list of words:

trie.add("sea shells", 3)
# same as trie.add(["sea", "shells"], 3)

Matching is greedy and will match the maximal length phrase:

print(trie.match("sea shells"))
# 3
print(trie.search("She sells sea shells by the sea shore."))
# [1, 3, 2]

The trie can be written to a JSON file with:

trie.to_json("sea.json")
# {
#   "She": {
#     "#": 1
#   },
#   "sea": {
#     "#": 2,
#     "shells": {
#       "#": 3
#     }
#   }
# }

Or restored from a JSON file with:

trie.from_json("sea.json")
print(trie.match("sea"))
# 2

The reserved key # is used to store the value in the JSON structure. You can still add a word that starts with # to the trie, and it will be protected with an additional prepended #:

trie.add("#She", 4)
trie.to_json("sea.json")
# {
#    "##She": {
# ...
print(trie.match("#She"))
# 4

Testing

Run the example above as a basic regression test with:

# grep "^    " README.md | sed 's/    //' | python