问题描述
我正在尝试使用FLEX和BISON解析传统语言(类似于"C").除了匹配的字符串，一切都运行良好.
I'm trying to parse a legacy language (which is similar to 'C') using FLEX and BISON. Everything is working nicely except for matching strings.
这种比较奇怪的传统语言不支持在字符串文字中用引号引起来，因此以下都是有效的字符串文字:
This rather odd legacy language doesn't support quoting characters in string literals, so the following are all valid string literals:
"hello"
""
"\"
我正在使用以下规则来匹配字符串文字:
I'm using the following rule to match string literals:
\".*\" { yylval.strval = _strdup( yytext ); return LIT_STRING; }
不幸的是，这是一个贪婪的匹配，因此它匹配如下代码:
Unfortunately this is a greedy match, so it matches code like the following:
"hello", "world"
作为单个字符串(hello", "world).
通常的非贪婪量词.*?在FLEX中似乎不起作用.有什么想法吗?
The usual non-greedy quantifier .*? doesn't seem to work in FLEX. Any ideas?
推荐答案
只禁止在引号之间使用引号.
Just prohibit having a quote in between the quotes.
\"[^"]*\"
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