大约有 42,000 项符合查询结果(耗时:0.0520秒) [XML]

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Is it possible for a computer to “learn” a regular expression by user-provided examples?

...ton, it is possible to learn some regular expressions by a program. Kearns and Valiant show some cases where it is not possible to learn a finite automaton. A related problem is learning hidden Markov Models, which are probabilistic automata that can describe a character sequence. Note that most mod...
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Most efficient way to check for DBNull and then assign to a variable?

...to avoid. By writing row.IsNull(columnName) you're reading it once already and reading it again. Not saying that will make a difference, but theoretically it can be less efficient.. – nawfal Feb 6 '13 at 16:31 ...
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What's the difference between and in servlet

...ort for general annotations such as @Required, @Autowired, @PostConstruct, and so on. <mvc:annotation-driven /> declares explicit support for annotation-driven MVC controllers (i.e. @RequestMapping, @Controller, although support for those is the default behaviour), as well as adding support f...
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Mutable vs immutable objects

...returning an array of strings from a method) but I'm having trouble understanding what the negative impacts are of this. What are the best practices around using mutable objects? Should you avoid them whenever possible? ...
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What are Transient and Volatile Modifiers?

Can someone explain what the transient and volatile modifiers mean in Java? 4 Answers ...
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When to use lambda, when to use Proc.new?

In Ruby 1.8, there are subtle differences between proc/lambda on the one hand, and Proc.new on the other. 14 Answers ...
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How can I create directory tree in C++/Linux?

... With C++17 or later, there's the standard header <filesystem> with function std::filesystem::create_directories which should be used in modern C++ programs. The C++ standard functions do not have the POSIX-specific explicit permissions (mode) argument, t...
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Why is extending native objects a bad practice?

... get a perfomance hit? Do they fear that somebody does it "the wrong way", and adds enumerable types to Object , practically destroying all loops on any object? ...
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View markdown files offline [closed]

... referring to showing the README.md file as it would come out in Github, and not as for editing purposes. 34 Answers ...
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Language Books/Tutorials for popular languages

...king on. The point of this post is to document some of the best tutorials and books for these languages. I will start the list with the best I can find, but hope you guys out there can help with better suggestions/new languages. Here is what I found: ...