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How does PHP 'foreach' actually work?

...ointer backup+restore mechanism is that changes to the IAP through reset() etc. usually do not impact foreach. For example, the following code executes as if the reset() were not present at all: $array = [1, 2, 3, 4, 5]; foreach ($array as &$value) { var_dump($value); reset($array); } /...
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How to import a module given the full path?

...on path can contain zip archives, "eggs" (a complex kind of zip archives), etc. Modules can be imported out of them. So the path elements are indeed containers of files, but they are not necessarily directories. – alexis Apr 30 '15 at 21:21 ...
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Unnecessary curly braces in C++?

...p myself happy (i.e. to separate out unrelated concerns, variable locality etc.), I use just this technique as elaborated by @unwind. – ossandcad Mar 16 '12 at 15:58 21 ...
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Email validation using jQuery

...ins becoming more common this regex may need modifying .systems and .poker etc are all valid TLDs now but would fail the regex check – Liath Sep 5 '14 at 7:35 3 ...
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Unit testing with Spring Security

...ent: session-scoped in a Servlet container, thread-scoped in a JUnit test, etc. The real limiting factor of a Singleton is when it provides an implementation that is inflexible to different environments. share | ...
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Programmatically find the number of cores on a machine

...umCPU = sysconf(_SC_NPROCESSORS_ONLN); FreeBSD, MacOS X, NetBSD, OpenBSD, etc. int mib[4]; int numCPU; std::size_t len = sizeof(numCPU); /* set the mib for hw.ncpu */ mib[0] = CTL_HW; mib[1] = HW_AVAILCPU; // alternatively, try HW_NCPU; /* get the number of CPUs from the system */ sysctl(mib, ...
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How to Correctly Use Lists in R?

...where the first element is a character vector, the second is a data frame, etc. In this case, you have created two different lists. x has four vectors, each of length 1. x2 has 1 vector of length 4: > length(x[[1]]) [1] 1 > length(x2[[1]]) [1] 4 So these are completely different lists. R l...
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JavaScript check if variable exists (is defined/initialized)

...(Assuming the variable could hold anything (string, int, object, function, etc.)) 28 Answers ...
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Extract hostname name from string

...uld be considered the root domain (i.e. www.食狮.公司.cn, b.c.kobe.jp, etc.). Read more about it here. Try: npm install --save psl Then with my "extractHostname" implementation run: let psl = require('psl'); let url = 'http://www.youtube.com/watch?v=ClkQA2Lb_iE'; psl.get(extractHostname(url...
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C# Lambda expressions: Why should I use them?

...# expressions in to the SQL expressions desired for filtering / ordering / etc. on the server side. share | improve this answer | follow | ...