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ʽڲʲôأеʱʹʽʱܶĽҪģôԭʲôأôͻһ𰸣

˽ʽıҪԣ

֪ʽιܿΪĳʽ

ʽࣺ

͵棺ı(text-directed)(regex-directed)档Jeffrey FriedlǳDFANFA档̸档ΪһЩǳõԣ硰ԡ(lazy quantifiers)ͷ(backreferences)ֻʵ֡ԺĿǰе档

׷ֱʹõıû򡰶ԡʱʵ֣Կ϶ʹõġ²ԣʽ<<regex|regex not>>Ӧõַregex notƥĽregexġregex notıġΪǡＱģܼеĽбҵĵһƥ 

ʽССܽ᣺

Ƿߵƥ䣬ҪĺҪһ㣺ʹԺпܷһáƥ䣬ҲǷߵƥ䡣

<<cat>>ӦõHe captured a catfish for his catȱȽ<<c>>͡HʧˡٱȽ<<c>>͡eҲʧˡֱĸַ<<c>>ƥˡc<<a>>ƥ˵ַַ<<t>>ûƥ䡰pҲʧˡټӵַ¼ƥԡֱʮַʼ<<cat>>ƥˡcatfishеġcatʽ漱еķصһƥĽټǷõƥ䡣

ʽݾܵϣʽ˽⡣