anchor.diff:      ;
   
   receive_statement
  -    : '('? RECEIVE (ALL | DISTINCT | top_clause | '*') 
  +    : '('? RECEIVE (ALL | DISTINCT | top_clause | '*')
         (LOCAL_ID '=' expression ','?)* FROM full_table_name
         (INTO table_variable=id (WHERE where=search_condition))? ')'?
       ;
  
positive.code:   :RETURNS TABLE
    (WITH function_option (',' function_option)*)?
    AS?
    RETURN select_statement 
    ;
  
  func_body_returns_table
  
negative.code:        BEGIN
             sql_clause*
             RETURN ret=expression ';'?
         END
         ;
  
  procedure_param
  