WordList

A WordList object is a list of unique words that can be used to test whether or not some word exists within that list.

It is most useful for large and/or long-lived lists. If you only want to test against a handful of words, it will likely be more efficient to use a table keyed by word instead.

WordLists have following functions:

WordList() WordList( filename ) addFromFile( filename ) addFromWordList( wordList )

addWord( word ) contains( word ) words() Operators

WordList()
WordList( filename )

Creates a new WordList object. You can either create an empty WordList (which you can populate later), or create a WordList from a file on disk. If you create one from a file on disk, each line of the file should contain a single word and nothing else.

Example

local cta = require 'cta'
local empty = cta.WordList()
local fromFile = cta.WordList( 'my-custom-wordlist.txt' )

WordList:addFromFile( filename )

Adds each line from the file specified in filename as a single word of the WordList.

Example

local cta = require 'cta'
local wordList = cta.WordList( 'wordlist1.txt' )

-- wordList will now contain all the unique words from the
-- files 'wordlist1.txt' and 'wordlist2.txt'
wordList:addFromFile( 'wordlist2.txt' )

WordList:addFromWordList( otherList )

Adds all the words from otherList to the current list.

Example

local cta = require 'cta'
local wordList1 = cta.WordList( 'wordlist.txt' )
local wordList2 = cta.WordList()

-- wordList2 will now contain the same words as wordList1
wordList2:addFromWordList( wordList1 )

WordList:addWord( word )

Adds a single word to the WordList.

Example

local cta = require 'cta'
local wordList = cta.WordList()

-- wordList will now contain a single word '佟掌柜'.
wordList:addWord( '佟掌柜' )

Performance Note: If you are repeatedly creating a WordList with a small number of words (e.g. in a loop), you will likely have better performance using a table keyed by word, rather than a WordList.

WordList:contains( word )

Tests to see if a word exists within in the list and returns true if so and false if not.

Example

local cta = require 'cta'
local wordList = cta.WordList( 'wordlist1.txt' )

if wordList:contains( '双煞' ) then
    print( 'Wordlist contains 双煞' )
else
    print( 'Wordlist does not contain 双煞' )
end

WordList:words()

Returns an iterator that will iterate over all words in the WordList. Each element of the iteration will be a string.

The order of iteration will be different than the order the words were added to the list, but will be consistent across all iterations.

Example

local cta = require 'cta'
local wordList = cta.WordList( 'wordlist.txt' )

for word in wordList:words() do
    ...
end

Operators

WordList objects also support the following Lua operators: +, - and #.