def block_yield(parent, indent)
      return unless accept :yield

      # Consume the newline from the end of the element
      error :yield unless accept(:line_feed).strip.empty?

      # Create a new node
      yield_node = [:yield, nil, {}, [], indent]

      parent[@children] << yield_node
    end
def block_yield(parent, indent)
      return unless accept :yield

      # Consume the newline from the end of the element
      error :yield unless accept(:line_feed).strip.empty?

      # Create a new node
      yield_node = [:yield, nil, {}, [], indent]

      parent[@children] << yield_node
    end
Match a yield with a explicit or implicit target

 yield target

 @param parent [Node] Parent node to which we append the definition