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CASE's shorthand variant evaluates an expression (usually a column) against a series of values. This variant is a bit shorter, and saves repeating the evaluated expression over and over again. The ELSE clause can still be used, though: SELECT Id, ItemId, Price, CASE Price WHEN 5 THEN 'CHEAP' ...

The struct template std::pair can bundle together exactly two return values, of any two types: #include <utility> std::pair<int, int> foo(int a, int b) { return std::make_pair(a+b, a-b); } With C++11 or later, an initializer list can be used instead of std::make_pair: C++11 ...

void Main() { unsafe { int[] a = {1, 2, 3}; fixed(int* b = a) { Console.WriteLine(b[4]); } } } Running this code creates an array of length 3, but then tries to get the 5th item (index 4). On my machine, this printed 1910457872, bu...

Classes are identifiers for the elements that they are assigned to. Use the class attribute to assign a class to an element. <div class="example-class"></div> To assign multiple classes to an element, separate the class names with spaces. <div class="class1 class2&...

The ID attribute of an element is an identifier which must be unique in the whole document. Its purpose is to uniquely identify the element when linking (using an anchor), scripting, or styling (with CSS). <div id="example-id"></div> You should not have two elements with th...

To add an image to a page, use the image tag. Image tags (img) do not have closing tags. The two main attributes you give to the img tag are src, the image source and alt, which is alternative text describing the image. <img src="images/hello.png" alt="Hello World"> Yo...

You can apply any kind of additional processing to the output by passing a callable to ob_start(). <?php function clearAllWhiteSpace($buffer) { return str_replace(array("\n", "\t", ' '), '', $buffer); } ob_start('clearAllWhiteSpace'); ?> <h1>Lorem Ipsum&l...

This uses the Dropbox Python SDK to upload a file to the Dropbox API from the local file as specified by file_path to the remote path as specified by dest_path. It also chooses whether or not to use an upload session based on the size of the file: f = open(file_path) file_size = os.path.getsize(fi...

When creating animations and other GPU-heavy actions, it's important to understand the will-change attribute. Both CSS keyframes and the transition property use GPU acceleration. Performance is increased by offloading calculations to the device's GPU. This is done by creating paint layers (parts of...

Suppose we have a plain object called prototype: var prototype = { foo: 'foo', bar: function () { return this.foo; } }; Now we want another object called obj that inherits from prototype, which is the same as saying that prototype is the prototype of obj var obj = Object.create(prototype); N...

Setting a filter applies to all channels that you will subscribe to from that particular client. This client filter excludes messages that have this subscriber's UUID set at the sender's UUID: NSString *expression = [NSString stringWithFormat:@"(uuid != '%@'", se...

This example uses the Dropbox .NET library to try to get the metadata for an item at a particular path, and checks for a NotFound error: try { var metadata = await this.client.Files.GetMetadataAsync("/non-existant path"); Console.WriteLine(metadata.Name); } catch (Dropbox.Api.A...

Constructor injection is the safest way of injecting dependencies that a whole class depends upon. Such dependencies are often referred to as invariants, since an instance of the class cannot be created without supplying them. By requiring the dependency to be injected at construction, it is guara...

Property injection allows a classes dependencies to be updated after it has been created. This can be useful if you want to simplify object creation, but still allow the dependencies to be overridden by your tests with test doubles. Consider a class that needs to write to a log file in an error co...

Method injection is a fine grained way of injecting dependencies into processing. Consider a method that does some processing based on the current date. The current date is hard to change from a test, so it is much easier to pass a date into the method that you want to test. public void ProcessRe...

Whilst extracting dependencies out of your code so that they can be injected makes your code easier to test, it pushes the problem further up the hierarchy and can also result in objects that are difficult to construct. Various dependency injection frameworks / Inversion of Control Containers have ...

If you want to squash the previous x commits into a single one, you can use the following commands: git reset --soft HEAD~x git commit Replacing x with the number of previous commits you want to be included in the squashed commit. Mind that this will create a new commit, essentially forgetting...

Commits can be squashed during a git rebase. It is recommended that you understand rebasing before attempting to squash commits in this fashion. Determine which commit you would like to rebase from, and note its commit hash. Run git rebase -i [commit hash]. Alternatively, you can type HE...

<?php echo esc_url( get_bloginfo( 'stylesheet_directory' ) ); ?> Output http://example.com/wp-content/themes/twentysixteen Alternatives Internally, get_bloginfo( 'stylesheet_directory' ) calls get_stylesheet_directory_uri(), so you may want to use that instead: <?php echo esc_url( ...

Dim input as String = Console.ReadLine() Console.ReadLine() will read the console input from the user, up until the next newline is detected (usually upon pressing the Enter or Return key). Code execution is paused in the current thread until a newline is provided. Afterwards, the next line of co...