我有一个bnf语法:
{
tokens = [
COLON = ":"
space=' '
word = 'regexp:[^\r\n\s\t@\$\{\}\(\)\|\#:<>]+'
nl = 'regexp:\r|\n|(\r\n)'
]
}
root ::= nlsp book_keyword COLON [space] book_title sections
book_keyword ::= 'Journal Book' | 'Fiction Book'
book_title ::= (! section (word | string) space?)+
sections ::= section+
section ::= nlsp section_keyword COLON [space] section_title {recoverWhile='sectionRecover'}
section_keyword ::= 'Section' | 'Content'
section_title ::= (!section (word | space | COLON))+
sectionRecover ::= !(nlsp| section_keyword)
nlsp ::= (NL| space)*
要测试的文字:
Fiction Book: Some Fiction
Section: Chapter One
Section: Chapter Two Section
Content: Chapter Three
如果我在第二个或之后的元素中出错,则一切正常,但是如果在第一个Sectio: Chapter One
中,所有psi树将被破坏。
答案 0 :(得分:0)
我看到几个问题: 1)您应该有空白令牌。像这样:
WHITESPACE="regexp:[ \n\r\t\f]"
因此,您不再需要空间和npsp
2)recoveryWhile规则应不带引号
3)部分恢复最有可能不正确的匹配空格