Tutorial by Examples: o

Evaluates its left operand, discards the resulting value, and then evaluates its rights operand and result yields the value of its rightmost operand. int x = 42, y = 42; printf("%i\n", (x *= 2, y)); /* Outputs "42". */ The comma operator introduces a sequence point between i...

This example uses the Car Table from the Example Databases. SELECT * FROM Cars WHERE TotalCost IN (100, 200, 300) This query will return Car #2 which costs 200 and Car #3 which costs 100. Note that this is equivalent to using multiple clauses with OR, e.g.: SELECT * FROM Cars WHERE TotalCos...

See full documentation on LIKE operator. This example uses the Employees Table from the Example Databases. SELECT * FROM Employees WHERE FName LIKE 'John' This query will only return Employee #1 whose first name matches 'John' exactly. SELECT * FROM Employees WHERE FName like 'John%' Ad...

A simple application showing the text "Hello World" in the center of the window. import QtQuick 2.3 import QtQuick.Window 2.0 Window { visible: true width: 640 height: 480 title: qsTr("Hello World") //The method qsTr() is used for translations from one la...

In order to get const char* access to the data of a std::string you can use the string's c_str() member function. Keep in mind that the pointer is only valid as long as the std::string object is within scope and remains unchanged, that means that only const methods may be called on the object. C++1...

The lambda keyword creates an inline function that contains a single expression. The value of this expression is what the function returns when invoked. Consider the function: def greeting(): return "Hello" which, when called as: print(greeting()) prints: Hello This can ...

This example shows the usage of the ILGenerator by generating code that makes use of already existing and new created members as well as basic Exception handling. The following code emits a DynamicAssembly that contains an equivalent to this c# code: public static class UnixTimeHelper { priva...

Branching in Subversion is very simple. In the simplest form, creating a new branch requires you to run the command against the remote repository's URLs. For example, let's create a new branch out of the mainline trunk: svn copy https://svn.example.com/svn/MyRepo/MyProject/trunk https://svn.example...

When you interact with the remote central repository using your private local workspace -- the working copy -- you can use repository-relative URL instead of direct URL to URL copy to create a new branch: svn copy "^/MyProject/trunk" "^/MyProject/branches/MyNewBranch" -m "C...

The working copy (WC) is your local and private workspace that you use to interact with the central Subversion repository. You use the working copy to modify the contents of your project and fetch changes committed by others. The working copy contains your project's data and looks and acts like a r...

Before publishing a package you have to version it. npm supports semantic versioning, this means there are patch, minor and major releases. For example, if your package is at version 1.2.3 to change version you have to: patch release: npm version patch => 1.2.4 minor release: npm version min...

Delete a file asynchronously: var fs = require('fs'); fs.unlink('/path/to/file.txt', function(err) { if (err) throw err; console.log('file deleted'); }); You can also delete it synchronously*: var fs = require('fs'); fs.unlinkSync('/path/to/file.txt'); console.log('file deleted'...

for (x <- 1 to 10) println("Iteration number " + x) This demonstrates iterating a variable, x, from 1 to 10 and doing something with that value. The return type of this for comprehension is Unit.

This demonstrates a filter on a for-loop, and the use of yield to create a 'sequence comprehension': for ( x <- 1 to 10 if x % 2 == 0) yield x The output for this is: scala.collection.immutable.IndexedSeq[Int] = Vector(2, 4, 6, 8, 10) A for comprehension is useful when you need to crea...

This shows how you can iterate over multiple variables: for { x <- 1 to 2 y <- 'a' to 'd' } println("(" + x + "," + y + ")") (Note that to here is an infix operator method that returns an inclusive range. See the definition here.) This creates the outp...

Consider this simple project with a flat directory structure: example |-- example.asd |-- functions.lisp |-- main.lisp |-- packages.lisp `-- tools.lisp The example.asd file is really just another Lisp file with little more than an ASDF-specific function call. Assuming your project depends o...

Can be used to shorten if/else operations. This comes in handy for returning a value quickly (i.e. in order to assign it to another variable). For example: var animal = 'kitty'; var result = (animal === 'kitty') ? 'cute' : 'still nice'; In this case, result gets the 'cute' value, because the v...

git cherry-pick <commit-hash> will apply the changes made in an existing commit to another branch, while recording a new commit. Essentially, you can copy commits from branch to branch. Given the following tree (Source) dd2e86 - 946992 - 9143a9 - a6fd86 - 5a6057 [master] \ ...

The background-image property is used to specify a background image to be applied to all matched elements. By default, this image is tiled to cover the entire element, excluding margin. .myClass { background-image: url('/path/to/image.jpg'); } To use multiple images as background-image, defi...

Method Chaining is a technique explained in Martin Fowler's book Domain Specific Languages. Method Chaining is summarized as Makes modifier methods return the host object, so that multiple modifiers can be invoked in a single expression. Consider this non-chaining/regular piece of code (ported...