Tutorial by Examples: p

$ mkdir hello-world $ cd hello-world $ tns create hello-world --ng $ tns platform add android #You can only add ios on an OSX machine Then ensure you have a device connected or an emulator running (if you don't, the default emulator should start or an error will be raised. I would recommend ge...

Dim aList as New List(Of String) aList.Add("one") aList.Add("two") aList.Add("three") For Each str As String in aList System.Console.WriteLine(str) Next Produces the following output: one two three Another option, would be to loop through using the ...

To start a bibliography you need to define your sources. Create a database file (like sources.bib) and include some content: @book{Doe1993, Author = {John Doe}, Publisher = {Earth University}, Title = {Creating a bibliography with biber}, Year = {1993}} You can then include y...

Related to Monads are F# computation expressions (CE). A programmer typically implements a CE to provide an alternative approach to chaining Monads, ie instead of this: let v = m >>= fun x -> n >>= fun y -> return_ (x, y) You can write this: let v = ce { let! x = m ...

Sometimes it is desirable to evaluate a nullable expression in an if-else fashion. The elvis operator, ?:, can be used in Kotlin for such a situation. For instance: val value: String = data?.first() ?: "Nothing here." The expression above returns "Nothing here" if data?.firs...

getTimeStemp is a unix representation of a datetime object. $date = new DateTime(); echo $date->getTimestamp(); this will out put an integer indication the seconds that have elapsed since 00:00:00 UTC, Thursday, 1 January 1970.

The & character appears first in entity references and must be escaped in element content or in attribute content. <?xml version="1.0"?> <document attribute="An ampersand is escaped as &"> An ampersand can also be escaped as & in element conte...

Attribute values can appear in simple or double quotes. The appropriate character must be escaped. <?xml version="1.0"?> <document quot-attribute="This is a "double quote" and this one is 'simple'" apos-attribute='This is a 'simple quot...

Type abbreviations allow you to create aliases on existing types to give them a more meaningful senses. // Name is an alias for a string type Name = string // PhoneNumber is an alias for a string type PhoneNumber = string Then you can use the alias just as any other type: // Create a recor...

Detailed instructions on getting xquery set up or installed.

In real world, connection and server delays could occur, to simulate delays in development environment Meteor._sleepForMs(ms); could be used Meteor.publish('USER_DATA', function() { Meteor._sleepForMs(3000); // Simulate 3 seconds delay return Meteor.users.find({}); });

select '123' * 2; To make the multiplication with 2 MySQL automatically converts the string 123 into a number. Return value: 246 The conversion to a number starts from left to right. If the conversion is not possible the result is 0 select '123ABC' * 2 Return value: 246 select 'A...

To load an image and place it on the canvas var image = new Image(); // see note on creating an image image.src = "imageURL"; image.onload = function(){ ctx.drawImage(this,0,0); } Creating an image There are several ways to create an image new Image() document.createEleme...

What's an image sprite? An image sprite is a single asset located within an image sprite sheet. An image sprite sheet is an image file that contains more than one asset that can be extracted from it. For example: The image above is an image sprite sheet, and each one of those stars is a sprite...

@Entity class Note { @Id Integer id; @Basic String note; @Basic int count; } Getters, setters etc. are ommitted for brevity, but they are not needed for JPA anyway. This Java class would map to the following table (depending on your database, here given in on...

@Entity class Note { @Id Integer id; @Basic String note; @Transient String parsedNote; String readParsedNote() { if (parsedNote == null) { /* initialize from note */ } return parsedNote; } } If your class needs fields that should ...

Suppose we want to get all product categories with total sales greater than 20. Here is a query without Common Table Expressions: SELECT category.description, sum(product.price) as total_sales FROM sale LEFT JOIN product on sale.product_id = product.id LEFT JOIN category on product.category_id ...

Suppose we want to query the "cheapest products" from the "top categories". Here is an example of query using Common Table Expressions -- all_sales: just a simple SELECT with all the needed JOINS WITH all_sales AS ( SELECT product.price as product_price, category.id a...

Skip lists are linked lists that allow you to skip to the correct node. This is a method which is way more fast than a normal singly linked list. It is basically a singly linked list but the pointers not going from one node to the next node, but skipping few nodes. Thus the name "Skip List&quo...

Partial method consists of the definition in one partial class declaration (as a common scenario - in the auto-generated one) and the implementation in another partial class declaration. using System; namespace PartialClassAndMethods { public partial class PartialClass // Auto-generated ...