anchor.diff:  	agree			= sanitize_integer(agree, -1, 65535, 0)
   	donor_pda		= sanitize_integer(agree, 1, donor_pdas.len, 1)
   	donor_hat		= sanitize_integer(agree, 1, donor_start_items.len, 1)
  +	purrbation 		= sanitize_integer(purrbation, 0, 1, initial(purrbation))
   
   	return 1
   
  
positive.code: 	S["undershirt"]			<< undershirt
  	S["socks"]				<< socks
  	S["backbag"]			<< backbag
  	S["purrbation"]			<< purrbation
  	S["species"]			<< pref_species.id
  	S["feature_mcolor"]					<< features["mcolor"]
  	S["feature_lizard_tail"]			<< features["tail_lizard"]
  
negative.code: 	S["undershirt"]			>> undershirt
  	S["socks"]				>> socks
  	S["backbag"]			>> backbag
  	S["feature_mcolor"]					>> features["mcolor"]
  	S["feature_lizard_tail"]			>> features["tail_lizard"]
  	S["feature_lizard_snout"]			>> features["snout"]
  