扩展的BBCode BNF

Question

有一个BBCode reference site。但Backus normal form是否存在BBCode？

Answer 1

我为personal project写了一个：

 <document> ::= <element> | <document> <element>
 <element> ::= <tag> | <content>
 <tag> ::= <opening_tag_1> | <opening_tag> <content> <closing_tag>
 <opening_tag> ::= <opening_tag_1> | <opening_tag_2>
 <opening_tag_1> ::= <tag_prefix> <tag_end>
 <opening_tag_2> ::= <tag_prefix> '=' <attr> <tag_end>
 <tag_prefix> ::= <tag_start> <tag_name>
 <tag_start> ::= '['
 <tag_end> ::= ']'
 <attr> ::= <character> | <attr> <character>
 <closing_tag> ::= <tag_start> '/' <tag_name> <tag_end>
 <tag_name> ::= <character_non-key> | <tag_name> <character_non-key_2>
 <content> ::= <character> | <content> <character>
 <character> ::= unicode
 <character_non-key> ::= unicode not including '[', '=', ']', '/'
 <character_non-key_2> ::= <character_non-key> | '/'