anchor.diff:  	;
   
   if
  -	: ~if id: statements :~
  -	| ~if id: statements :else: statements :~
  +	: '~if' id ':' statements ':~'
  +	| '~if' id ':' statements ':else:' statements ':~'
   	;
   
   
   for
  -	: ~for prop_name in id: statements :~
  -	| ~for prop_name in id: statements :else: statements :~
  +	: '~for' prop_name 'in' id ':' statements ':~'
  +	| '~for' prop_name 'in' id ':' statements ':else:' statements ':~'
   	;
   
   text
  
positive.code: 	;
  
  prop_name_body
  	: _
  	| prop_name_head
  	;
  
  
negative.code: 
  id
  	: prop_name
  	| prop_name '.' id
  	;
  
  // ---------------------------------------------
  