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How do I get current date/time on the Windows command line in a suitable format for usage in a file/
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On my system %TIME% returns values like " 0:01:15" and " 3:15:12" and the %%a%%b code in the answer gives a leading space like " 001" and " 315". To get a four digit hhmm use this: For /f "tokens=1-2 delims=/: " %%a in ("%TIME%") do (if %%a LSS 10 (set mytime=0%%a%%b) else (s...
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...
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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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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When would anyone use a union? Is it a remnant from the C-only days?
...pace to work with, or when you're developing an API (or something similar) and you want to force the end user to have only one instance of several objects/types at one time. Are these two guesses even close to right?
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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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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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How can I create directory tree in C++/Linux?
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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...
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...
Can PHP cURL retrieve response headers AND body in a single request?
Is there any way to get both headers and body for a cURL request using PHP? I found that this option:
13 Answers
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