Class: Kotoshu::Grammar::PatternMatchers::DoubleNegativeMatcher

Inherits:
BaseMatcher
  • Object
show all
Defined in:
lib/kotoshu/grammar/pattern_matchers/double_negative_matcher.rb

Overview

Matcher for double negative rules.

This matcher detects when multiple negative words appear within a certain distance.

Instance Method Summary collapse

Methods inherited from BaseMatcher

#initialize

Constructor Details

This class inherits a constructor from Kotoshu::Grammar::PatternMatchers::BaseMatcher

Instance Method Details

#match(tokens, rule) ⇒ Array<Hash>

Match tokens against the double negative pattern.

Parameters:

  • tokens (Array<Hash>) —

    Array of token hashes

  • rule (Rule) —

    The rule being checked

Returns:

  • (Array<Hash>) —

    Array of error hashes



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# File 'lib/kotoshu/grammar/pattern_matchers/double_negative_matcher.rb', line 18

def match(tokens, rule)
  errors = []
  exceptions = rule.exceptions || {}
  exception_phrases = exceptions['phrases'] || []

  conditions = @pattern['conditions'] || []
  distance_condition = conditions.find { |c| c['type'] == 'distance_check' }
  max_distance = distance_condition&.dig('max_distance') || 15

  negative_indices = []
  tokens.each_with_index do |token, idx|
    word = token[:token]&.downcase
    next unless is_negative?(word)

    # Skip "not only... but also" pattern
    next if in_exception_phrase?(idx, tokens, exception_phrases)

    negative_indices << idx
  end

  negative_indices.each_cons(2) do |idx1, idx2|
    pos1 = tokens[idx1][:position]
    pos2 = tokens[idx2][:position]
    distance = pos2 - pos1
    next if distance > max_distance

    error = build_error(tokens, idx1, idx2, rule)
    errors << error if error
  end
  errors
end