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Google Perf Tools also provides a CPU profiler, with a slightly friendlier interface. To use it: Install Google Perf Tools Compile your code as usual Add the libprofiler profiler library to your library load path at runtime Use pprof to generate a flat execution profile, or a callgraph diagram...

The std::nth_element algorithm takes three iterators: an iterator to the beginning, nth position, and end. Once the function returns, the nth element (by order) will be the nth smallest element. (The function has more elaborate overloads, e.g., some taking comparison functors; see the above link for...

.exr -1 gives you details about the last exception thrown. !analyze -v usually does a good job as well. For .NET, the command !pe of the SOS extension shows details about the .NET exception that was thrown.

Print the path to the active developer directory (selected Xcode) xcode-select -p Select a different version of Xcode, e.g. Beta sudo xcode-select -s /Applications/Xcode-beta.app Reset to the default version of Xcode sudo xcode-select -r This is equivalent to running sudo xcode-select -s /Appl...

Ref returns and ref locals are useful for manipulating and returning references to blocks of memory instead of copying memory without resorting to unsafe pointers. Ref Return public static ref TValue Choose<TValue>( Func<bool> condition, ref TValue left, ref TValue right) { ...

We're going to use the expression tree API to create a CalculateSalesTax tree. In plain English, here's a summary of the steps it takes to create the tree. Check if the product is taxable If it is, multiply the line total by the applicable tax rate and return that amount Otherwise return 0 ...

Sometimes we want to look at what is sent and received in the SOAP request. The following methods will return the XML in the request and response: SoapClient::__getLastRequest() SoapClient::__getLastRequestHeaders() SoapClient::__getLastResponse() SoapClient::__getLastResponseHeaders() For ex...

array_flip function will exchange all keys with its elements. $colors = array( 'one' => 'red', 'two' => 'blue', 'three' => 'yellow', ); array_flip($colors); //will output array( 'red' => 'one', 'blue' => 'two', 'yellow' => 'three' )

For the built-in shift operator, the right operand must be nonnegative and strictly less than the bit width of the promoted left operand. Otherwise, the behavior is undefined. const int a = 42; const int b = a << -1; // UB const int c = a << 0; // ok const int d = a << 32; // ...

In this example, a destructor is explicitly invoked for an object that will later be automatically destroyed. struct S { ~S() { std::cout << "destroying S\n"; } }; int main() { S s; s.~S(); } // UB: s destroyed a second time here A similar issue occurs when a st...

To change a text file is not easy because its content must be moved around. For small files easiest method is to read its content in memory and then write back modified text. In this example we read all lines from a file and drop all blank lines then we write back to original path: File.WriteAllLi...

This snippet is an helper function to enumerate all files older than a specified age, it's useful - for example - when you have to delete old log files or old cached data. static IEnumerable<string> EnumerateAllFilesOlderThan( TimeSpan maximumAge, ...

echo off cls sqlcmd.exe -S "your server name" -U "sql user name" -P "sql password" -d "name of databse" -Q "here you may write your query/stored procedure" Batch files like these can be used to automate tasks, for example to make backups of ...

Basic Error Handling By default, Express will look for an 'error' view in the /views directory to render. Simply create the 'error' view and place it in the views directory to handle errors. Errors are written with the error message, status and stack trace, for example: views/error.pug html bo...

It's a good practice to run NodeJS apps controlled by process managers. Process manager helps to keep application alive forever, restart on failure, reload without downtime and simplifies administrating. Most powerful of them (like PM2) have a built-in load balancer. PM2 also enables you to manage ...

This command has several related yet distinct forms. del v If v is a variable, the command del v removes the variable from its scope. For example: x = 5 print(x) # out: 5 del x print(x) # NameError: name 'f' is not defined Note that del is a binding occurence, which means that unless expl...

This query returns all the documents with element "company" and its value as "marklogic" cts:element-value-query(xs:QName('company'), 'marklogic'))

The following query returns the documents which have an element named "company" - cts:element-value-query( xs:QName('company'), '*', ("wildcarded"))) The following query returns the documents which have an element named "company" with an attribute named "name&...

The example is for illustration purpose of using libraries and helpers and not a valid code. Do not copy / paste it on your projects. HELPER helpers/sendEmail_helper.php if ( ! function_exists('sendEmail')) { function sendEmail($email, $subject, $message, $lang, $cc = null, $file = null) { ...

But you don't just want a plain text email. You want a pretty html email. Set your config file as html: $config['mailtype'] = 'html'; If you want to pass data (like a username for example) to the html email, put them in an array: $data = array('name' => $name, 'email' => ...