class Language::Matcher

Matcher

Matcher derives from Ruby Quiz #103, the DictionaryMatcher quiz.

Attributes

word_count[R]

Public Class Methods

new() click to toggle source

Create a DictionaryMatcher with no words in it

# File lib/language/matcher.rb, line 25
def initialize
  @trie = {}
  @word_count = 0
end

Public Instance Methods

<<(word) click to toggle source

Alias for: add

===(text) click to toggle source

Case equality. Similar to =~.

Alias for: =~

=~(text) click to toggle source

Determines whether one of the words in the DictionaryMatcher is a substring of string. Returns the index of the match if found, nil if not found.

# File lib/language/matcher.rb, line 88
def =~ text
  internal_match(text){|md| return md.index}
  nil
end

Also aliased as: ===

add(word) click to toggle source

Add a word to the DictionaryMatcher

# File lib/language/matcher.rb, line 31
def add(word)
  @word_count += 1
  container = @trie
  containers=[]

  i=0
  word.each_byte do |b|
    container[b] = {} unless container.has_key? b
    container[:depth]=i
    containers << container
    container = container[b]
    i+=1
  end
  containers << container

  container[0] = true # Mark end of word
  container[:depth]=i

  ff=compute_failure_function word
  ff.zip(containers).each do |pointto,container|
    container[:failure]=containers[pointto] if pointto
  end

  self

end

Also aliased as: <<

include?(word) click to toggle source

Determine whether string was previously added to the Trie.

# File lib/language/matcher.rb, line 75
def include?(word)
  container = @trie
  word.each_byte do |b|
    break unless container.has_key? b
    container = container[b]
  end
  container[0]
end

inspect() click to toggle source

# File lib/language/matcher.rb, line 20
def inspect
  to_s
end

match(text) click to toggle source

Determine whether one of the words in the DictionaryMatcher is a substring of string. Returns a DictionaryMatcher::MatchData object if found, nil if not found.

# File lib/language/matcher.rb, line 97
def match text
  internal_match(text){|md| return md}
  nil
end

scan(text, &block) click to toggle source

Scans string for all occurrances of strings in the DictionaryMatcher. Overlapping matches are skipped (only the first one is yielded), and when some strings in the DictionaryMatcher are substrings of others, only the shortest match at a given position is found.

# File lib/language/matcher.rb, line 135
def scan(text, &block)
  matches=[]
  block= lambda{ |md| matches << md } unless block
  internal_match(text,&block)
  matches
end