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Is if(items != null) superfluous before foreach(T item in items)?
...wever you can do something like this:
List<string> items = null;
foreach (var item in items ?? new List<string>())
{
item.Dump();
}
but you might check performance of it. So I still prefer having if (items != null) first.
Based on Eric's Lippert suggestion I changed code to:
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Change R default library path using .libPaths in Rprofile.site fails to work
I am running R on Windows, not as an administrator. When I install a package, the following command doesn't work:
15 Answer...
Which is the correct shorthand - “regex” or “regexp” [closed]
Most of us computer programmers are pretty obsessed about correct terminology. I certainly am, especially because sometimes changing just one character in a word can drastically change its meaning.
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Can you use a trailing comma in a JSON object?
When manually generating a JSON object or array, it's often easier to leave a trailing comma on the last item in the object or array. For example, code to output from an array of strings might look like (in a C++ like pseudocode):
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What is that “total” in the very first line after ls -l? [closed]
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You can find the definition of that line in the ls documentation for your platform. For coreutils ls (the one found on a lot of Linux systems), the information can be found via info coreutils ls:
For each directory that is listed, preface the files with a line
`total BLOCKS', whe...
Exporting a function in shell
Please tell me how to export a function in parent shell (bash, sh or ksh) so that the function will be available to all the child process launced from the parent process?
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Building vs. Compiling (Java)
...he steps required to create a "deliverable" of your software. In the Java world, this typically includes:
Generating sources (sometimes).
Compiling sources.
Compiling test sources.
Executing tests (unit tests, integration tests, etc).
Packaging (into jar, war, ejb-jar, ear).
Running health checks ...
Open Graph namespace declaration: HTML with XMLNS or head prefix?
I have seen conflicting information on how to best implement Open Graph namespaces. Specifically, the Open Graph website uses a few different methods, and the Facebook Open Graph examples use other methods.
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Force R not to use exponential notation (e.g. e+10)?
Can I force R to use regular numbers instead of using the e+10 -like notation? I have:
4 Answers
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Does PHP have threading?
...ry. Depending on what you are trying to do and how complex it is, this may or may not be an option.
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