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API ScriptAuthor: Brian
Version: 1.1
Last Modified: 2016-03-09
Code: levenshteinDistance
Dependencies: None
Conflicts: None

levenshteinDistance is a string comparison function. The metric was developed by Vladimir Levenshtein in 1965. The function tracks the difference between two strings based on single-character changes. In other words, the number of insertions, deletions, and substitutions required to change the first string into the second. This metric is useful for deciding what strings are "close" to being the same, such as finding a partial match against a player or character name.

The levenshteinDistance function is added to String.prototype, meaning it can be treated as a function of string objects.

Original JavaScript implementation from





The string to compare against str.

Return Value

levenshteinDistance returns an integer of the total number of insertions, deletions, and substitutions required to change str into otherStr.


The distance between "kitten" and "sitting" is 3:

  1. kitten → sitten (substitute "s" for "k")
  2. sitten → sittin (substitute "i" for "e")
  3. sittin → sitting (insert "g")
on('chat:message', function(msg) {
    var params = msg.content.splitArgs(),
        command = params.shift().substring(1).toLowerCase(),
        characterName = params[0],
        potentialCharacters, foundCharacter;

    if (msg.type === 'api' && command === 'echocharacter') {
        potentialCharacters = filterObjs(function(obj) { return obj.get('type') === 'character' && obj.get('name').indexOf(who) >= 0; });
        foundCharacter = _.sortBy(potentialCharacters, function(chr) {
            return chr.get('name').toLowerCase().levenshteinDistance(who.toLowerCase());

        if (foundCharacter) {
            sendChat('System', characterName + ' interpreted as ' + foundCharacter.get('name'));
        } else {
            sendChat('System', 'Could not find character for ' + characterName);


v1.1 (2016-03-09)

  • Update for one-click install

v1.0 (2015-01-08)

  • Release