Class: Attentive::Matcher

Inherits:
Object
  • Object
show all
Defined in:
lib/attentive/matcher.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(phrase, cursor, params = {}) ⇒ Matcher

Returns a new instance of Matcher.



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# File 'lib/attentive/matcher.rb', line 7

def initialize(phrase, cursor, params={})
  @phrase = phrase
  @cursor = cursor
  @pos = params.fetch(:pos, 0)
  @match_params = params.each_with_object({}) { |(key, value), new_hash| new_hash[key] = value if %i{listener message}.member?(key) }
  @pos += 1 while phrase[pos] && phrase[pos].whitespace?
  @match_data = {}
  @state = :matching
end

Instance Attribute Details

#cursor ⇒ Object (readonly)

Returns the value of attribute cursor.



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# File 'lib/attentive/matcher.rb', line 5

def cursor
  @cursor
end

#phrase ⇒ Object (readonly)

Returns the value of attribute phrase.



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# File 'lib/attentive/matcher.rb', line 5

def phrase
  @phrase
end

#pos ⇒ Object (readonly)

Returns the value of attribute pos.



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# File 'lib/attentive/matcher.rb', line 5

def pos
  @pos
end

Instance Method Details

#match! ⇒ Object 



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# File 'lib/attentive/matcher.rb', line 25

def match!
  while token = cursor.peek
    if token.ambiguous?
      unless match_subphrase!(token.possibilities)
        @state = :mismatch
        break
      end
      @pos += 1 while phrase[pos] && phrase[pos].whitespace?

    elsif match_data = phrase[pos].matches?(cursor)
      if match_data.is_a?(MatchData)
        new_character_index = cursor.offset + match_data.to_s.length
        @match_data.merge! Hash[match_data.names.zip(match_data.captures)]

        # Advance the cursor to the first token after the regexp match
        cursor_pos = cursor.tokens.index { |token| token.pos >= new_character_index }
        cursor_pos = cursor.tokens.length unless cursor_pos
        cursor.instance_variable_set :@pos, cursor_pos
        @pos += 1
      else
        @match_data.merge!(match_data) unless match_data == true
        @pos += 1
      end
      @pos += 1 while phrase[pos] && phrase[pos].whitespace?
      @state = :found


      # -> This is the one spot where we instantiate a Match
      return Attentive::Match.new(phrase, @match_params.merge(match_data: @match_data)) if pos == phrase.length

    elsif !token.skippable?
      @state = :mismatch
      break
    end

    cursor.pop
    break unless cursor.peek
    while cursor.peek.whitespace?
      cursor.pop
      break unless cursor.peek
    end
  end

  nil
end

#match_subphrase!(subphrases) ⇒ Object 



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# File 'lib/attentive/matcher.rb', line 71

def match_subphrase!(subphrases)
  subphrases.each do |subphrase|
    matcher = Matcher.new(phrase, Cursor.new(subphrase), pos: pos)
    matcher.match!
    unless matcher.mismatch?
      @pos = matcher.pos
      return true
    end
  end

  false
end

#matching? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/attentive/matcher.rb', line 17

def matching?
  @state == :matching
end

#mismatch? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/attentive/matcher.rb', line 21

def mismatch?
  @state == :mismatch
end