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Checking for empty arrays: count vs empty
...it's only personal preference. Some people might say empty is faster (e.g. http://jamessocol.com/projects/count_vs_empty.php) while others might say count is better since it was originally made for arrays. empty is more general and can be applied to other types.
php.net gives the following warning ...
When to use the brace-enclosed initializer?
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
Forward an invocation of a variadic function in C
...a va_list instead of a variable number of arguments, you can't do it. See http://c-faq.com/varargs/handoff.html.
Example:
void myfun(const char *fmt, va_list argp) {
vfprintf(stderr, fmt, argp);
}
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Free space in a CMD shell
... can alter the output by various command-line options.
You can get it from http://www.paulsadowski.com/WSH/cmdprogs.htm, http://unxutils.sourceforge.net/ or somewhere else. It's a standard unix-util like du.
df -h will show all your drive's used and available disk space. For example:
M:\>df -h
F...
HttpClient.GetAsync(…) never returns when using await/async
...(within the ASP.NET request context).
AsyncAwait_GetSomeDataAsync executes HttpClient.GetAsync (within the ASP.NET request context).
The HTTP request is sent out, and HttpClient.GetAsync returns an uncompleted Task.
AsyncAwait_GetSomeDataAsync awaits the Task; since it is not complete, AsyncAwait_Ge...
SQL Server: Examples of PIVOTing String data
...
From http://blog.sqlauthority.com/2008/06/07/sql-server-pivot-and-unpivot-table-examples/:
SELECT CUST, PRODUCT, QTY
FROM Product) up
PIVOT
( SUM(QTY) FOR PRODUCT IN (VEG, SODA, MILK, BEER, CHIPS)) AS pvt) p
UNPIVOT
(QTY FOR PROD...
How do I make a column unique and index it in a Ruby on Rails migration?
.... :column_name_n], unique: true, name: 'my_custom_index_name'
More info - http://apidock.com/rails/ActiveRecord/ConnectionAdapters/SchemaStatements/add_index
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What is the fastest way to get the value of π?
...way (more universal solution) is:
look up Pi on the Internet, e.g. here:
http://www.eveandersson.com/pi/digits/1000000 (1 million digits .. what's your floating point precision? )
or here:
http://3.141592653589793238462643383279502884197169399375105820974944592.com/
or here:
http://en.wikiped...
Put content in HttpResponseMessage object?
Several months ago, Microsoft decided to change up the HttpResponseMessage class. Before, you could simply pass a data type into the constructor, and then return the message with that data, but not anymore.
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Performance of Find() vs. FirstOrDefault() [duplicate]
...foreach loop to do the checking. List<T>.Find() is not part of Linq (http://msdn.microsoft.com/en-us/library/x0b5b5bc.aspx), and is likely using a standard for loop from 0 to Count (or another fast internal mechanism probably operating directly on its internal/wrapped array). By getting rid of...