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Source Code

# File action_controller/routing/segments.rb, line 83
def build_pattern(pattern)
  escaped = Regexp.escape(value)
  if optional? && ! pattern.empty?
    "(?:#{Regexp.optionalize escaped}\\Z|#{escaped}#{Regexp.unoptionalize pattern})"
  elsif optional?
    Regexp.optionalize escaped
  else
    escaped + pattern
  end
end