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XML <Galaxy> <name>Milky Way</name> <CelestialObject name="Earth" type="planet"/> <CelestialObject name="Sun" type="star"/> </Galaxy> XPATH /Galaxy/*[ends-with(lower-case(@type),'tar')] or //*[ends-w...

Schema Statics are methods that can be invoked directly by a Model (unlike Schema Methods, which need to be invoked by an instance of a Mongoose document). You assign a Static to a schema by adding the function to the schema's statics object. One example use case is for constructing custom queries:...

A Set is a Collection that cannot contain duplicate elements. It models the mathematical set abstraction. Set have its implementation in various classes like HashSet, TreeSet, LinkedHashSet. For example: HashSet: Set<T> set = new HashSet<T>(); Here T can be String, Integer or any ...

A declaration introduces an identifier and describes its type, be it a type, object, or function. A declaration is what the compiler needs to accept references to that identifier. These are declarations: extern int bar; extern int g(int, int); double f(int, double); /* extern can be omitted for f...

The =~ operator attempts to match a regular expression (set apart by /) to a string: my $str = "hello world"; print "Hi, yourself!\n" if $str =~ /^hello/; /^hello/ is the actual regular expression. The ^ is a special character that tells the regular expression to start with ...

(Collects a certain number of total items from 2-3 inputs and groups them into a Tuple of collections of data items) BatchedJoinBlock<T1, T2,…> is in a sense a combination of BatchBlock and JoinBlock<T1, T2,…>. Whereas JoinBlock<T1, T2,…> is used to aggregate one input from each ...

(Groups a certain number of sequential data items into collections of data items) BatchBlock combines N single items into one batch item, represented as an array of elements. An instance is created with a specific batch size, and the block then creates a batch as soon as it’s received that number o...

Public Function GetUserFirstName(UserName As String) As String Dim Firstname As String = "" 'Specify the SQL that you want to use including a Parameter Dim SQL As String = "select firstname from users where username=@UserName" 'Provide a Data Sourc...

Java and most other languages store negative integral numbers in a representation called 2's complement notation. For a unique binary representation of a data type using n bits, values are encoded like this: The least significant n-1 bits store a positive integral number x in integral representati...

Random and ThreadLocalRandom are good enough for everyday use, but they have a big problem: They are based on a linear congruential generator, an algorithm whose output can be predicted rather easily. Thus, these two classes are not suitable for cryptographic uses (such as key generation). One can ...

Drag 1 textbox and 1 button Double click the button1 and you will be transferred to the Button1_Click event Public Class Form1 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click End Sub End Class Type the name of the object that you want to target, ...

Using sw As New System.IO.StreamWriter("path\to\file.txt") sw.WriteLine("Hello world") End Using The use of a Using block is recommended good practice when using an object that Implements IDisposable

/** * returns a array of random numbers with no duplicates * @param range the range of possible numbers for ex. if 100 then it can be anywhere from 1-100 * @param length the length of the array of random numbers * @return array of random numbers with no duplicates. */ public static int[] ...

Creating backpressured data sources is the relatively easier task when dealing with backpressure in general because the library already offers static methods on Observable that handle backpressure for the developer. We can distinguish two kinds of factory methods: cold "generators" that ei...

Basic HTTP calls don't provide code-reusability, however. And they can get confused with all the other features you're trying to implement. For those reasons, it's common to implement an API wrapper. Foo = { identify: function(input){ return Http.get('http://foo.net/api/identify/' + input...

After creating an API wrapper, it's likely that you may want to create an Atmosphere package to redistribute it and share it between applications. The files of your package will probably look something like this. packages/foo-api-wrapper/package.js packages/foo-api-wrapper/readme.md packages/foo-...

At this point, you're still building your package, so you'll need to add the package to your application: meteor add myaccount:foo And eventually publish it to Atmosphere: meteor publish myaccount:foo

We can also use macros for making code easier to read and write. For example we can implement macros for implementing the foreach construct in C for some data structures like singly- and doubly-linked lists, queues, etc. Here is a small example. #include <stdio.h> #include <stdlib.h>...

This attribute can change the background of the Status Bar icons (at the top of the screen) to white. <style name="AppTheme" parent="Theme.AppCompat"> <item name="android:windowLightStatusBar">true</item> </style>

The navigation bar (at the bottom of the screen) can be transparent. Here is the way to achieve it. <style name="AppTheme" parent="Theme.AppCompat"> <item name="android:windowTranslucentNavigation">true</item> </style> The Status Bar (t...