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It is also possible to use Scala's string interpolation feature to create elaborate extractors (pattern matchers), as perhaps most famously employed in the quasiquotes API of Scala macros. Given that n"p0${i0}p1" desugars to new StringContext("p0", "p1").n(i0), it is p...

The r method implicitly provided via scala.collection.immutable.StringOps produces an instance of scala.util.matching.Regex from the subject string. Scala's triple-quoted string syntax is useful here, as you do not have to escape backslashes as you would in Java: val r0: Regex = """(...

.message color: white .message-important @extend .message background-color: red This will take all of the styles from .message and add them to .message-important. It generates the following CSS: .message, .message-important { color: white; } .message-important { background-...

.message color: white .important background-color: red .message-important @extend .message, .important In the above code @extend is used in one line to add multiple classes' code to .message-important, however, it is possible to use one extend per line like this: .message-importan...

.message color: white background: black .message-important @extend .message font-weight: bold .message-error @extend .message-important font-style: italic This code causes .message-error to extend from .message-important, which means that it will contain code from both .me...

Sometimes, you may want an @extend to be optional, and not require the specified class to exist in your code. .message-important @extend .message !optional background: red This will result in the following CSS: .message-important { background: red; } Disclaimer: This is useful duri...

Natively, Jenkins runs on port 8080. We can establish a proxy from port 80 -> 8080 so Jenkins can be accessed via: http://<url>.com instead of the default http://<url>.com:8080 Begin by installing Nginx. sudo aptitude -y install nginx Remove the default settings for Nginx c...

The .indexOf method returns the index of a substring inside another string (if exists, or -1 if otherwise) 'Hellow World'.indexOf('Wor'); // 7 .indexOf also accepts an additional numeric argument that indicates on what index should the function start looking "harr dee harr dee harr&quot...

The ANSI CL standard uses an extended EBNF syntax notation. The documentation duplicated on Stackoverflow should use the same syntax notation to reduce confusion. Example: specialized-lambda-list::= ({var | (var parameter-specializer-name)}* [&optional {var | (var [initform [supp...

import java.io.*; import java.net.Socket; public class Main { public static void main(String[] args) throws IOException {//We don't handle Exceptions in this example //Open a socket to stackoverflow.com, port 80 Socket socket = new Socket("stackoverflow.com",8...

There are several good examples of using lambdas as a FunctionalInterface in simple scenarios. A fairly common use case that can be improved by lambdas is what is called the Execute-Around pattern. In this pattern, you have a set of standard setup/teardown code that is needed for multiple scenarios ...

JSON (JavaScript Object Notation) syntax is based on a subset of JavaScript (see also json.org). A valid JSON expression can be one of the following data types simple data types: String, Number, Boolean, Null composite data types: Value, Object, Array Simple data types A JSON string has to ...

The password in a credential object is an encrypted [SecureString]. The most straightforward way is to get a [NetworkCredential] which does not store the password encrypted: $credential = Get-Credential $plainPass = $credential.GetNetworkCredential().Password The helper method (.GetNetworkCrede...

This will create a composite index of both keys, mystring and mydatetime and speed up queries with both columns in the WHERE clause. CREATE INDEX idx_mycol_myothercol ON my_table(mycol, myothercol) Note: The order is important! If the search query does not include both columns in the WHERE claus...

On Debian-based distributions, including Ubuntu, the most straightforward way is to use the .deb installation file. Go to the Scala website. Choose the version you want to install then scroll down and look for scala-x.x.x.deb. You can install the scala deb from command line: sudo dpkg -i scala-x.x...

Most developers encounter backpressure when their application fails with MissingBackpressureException and the exception usually points to the observeOn operator. The actual cause is usually the non-backpressured use of PublishSubject, timer() or interval() or custom operators created via create(). ...

If efficiency is important, a fast way to iterate over pixels in a cv::Mat object is to use its ptr<T>(int r) method to obtain a pointer to the beginning of row r (0-based index). According to the matrix type, the pointer will have a different template. For CV_8UC1: uchar* ptr = image.ptr&...

Add the following code to functions.php to remove it from everyone except the Administrator user level: add_action('after_setup_theme', 'no_admin_bar'); function no_admin_bar() { if (!current_user_can('administrator') && !is_admin()) { show_admin_bar(false); ...

This example is a basic setup for unittesting the StringBuilder.toString() using junit. import static org.junit.Assert.assertEquals; import org.junit.Test; public class StringBuilderTest { @Test public void stringBuilderAppendShouldConcatinate() { StringBuilder stringBui...

Strategy: Strategy is a behavioural pattern, which allows to change the algorithm dynamically from a family of related algorithms. UML of Strategy pattern from Wikipedia : import java.util.*; /* Interface for Strategy */ interface OfferStrategy { public String getName(); public dou...