erb.treetop

grammar ERB
  rule document
    (whitespace / text / erb / self_closing_tag / open_tag / close_tag)* {
      def content
        elements.map{ |e| e.content }
      end
    }
  end

  rule whitespace
    [\s]+ {
      def content
        [:whitespace, text_value]
      end
    }
  end

  rule text
    [^<]+ {
      def content
        [:text, text_value]
      end
    }
  end

  rule open_erb_tag
    "<%" {
      def content
        [:open_erb_tag]
      end
    }
  end

  rule open_tag
    "<" name attribute_list ">" {
      def content
        [:open_tag, elements[1].content, elements[2].content]
      end
    }
  end

  rule self_closing_tag
    "<" name attribute_list [\s]* "/>" {
      def content
        [:self_closing_tag, elements[1].content, elements[2].content]
      end
    }
  end

  rule close_erb_tag
    "%>" {
      def content
        [:close_erb_tag]
      end
    }
  end

  rule close_tag
    "</" name ">" {
      def content
        [:close_tag, elements[1].content]
      end
    }
  end

  rule name
    [A-Za-z0-9]+ {
      def content
        text_value
      end

      def quote
        nil
      end
    }
  end

  rule attribute_list
    attribute* {
      def content
        elements.inject({}){ |hash, e| hash.merge(e.content) }
      end
    }
  end

  rule erb
    open_erb_tag ruby_code close_erb_tag {
      def content
        [:erb, elements[1].content]
      end
    }
  end

  rule attribute
    [\s]+ name "=" (quoted_value / single_quoted_value / name) {
      def content
        {elements[1].content => [elements[3].quote, elements[3].content]}
      end
    }
  end

  rule ruby_code
    [^%]+ {
      def content
        text_value
      end
    }
  end

  rule single_quoted_value
    "'" [^']* "'" {
      def content
        elements[1].text_value
      end

      def quote
        "'"
      end
    }
  end

  rule quoted_value
    '"' [^"]* '"' {
      def content
        elements[1].text_value
      end

      def quote
        '"'
      end
    }
  end
end