anchor.diff:  	| SHA1
   	| SHA256
   	| SHA512
  -	| CRC8
  -	| CRC16
   	| CRC32
   	| HMACMD5
   	| HMACSHA1
  
positive.code: SHA1: 'SHA1';
  SHA256: 'SHA256';
  SHA512: 'SHA512';
  CRC8: 'CRC8';
  CRC16: 'CRC16';
  CRC32: 'CRC32';
  HMACMD5: 'HMACMD5';
  HMACSHA1: 'HMACSHA1';
  
negative.code: 	| BASE64URLTOTEXT '(' expr (',' expr)? ')'					# BASE64URLTOTEXT_fun2
  	| TEXTTOBASE64 '(' expr (',' expr)? ')'						# TEXTTOBASE64_fun2
  	| TEXTTOBASE64URL '(' expr (',' expr)? ')'					# TEXTTOBASE64URL_fun2
  	| REGEX '(' expr ',' expr ')'								# REGEX_fun2
  	| REGEXREPALCE '(' expr ',' expr ',' expr ')'				# REGEXREPALCE_fun2
  	| ISREGEX '(' expr ',' expr ')'								# ISREGEX_fun2
  	| GUID '(' ')'												# GUID_fun2
  