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Using "assert False"

While developing, inserting the following line to your code: assert False, value will cause django to raise an AssertionError with the value supplied as an error message when this line is executed. If this occurs in a view, or in any code called from a view, and DEBUG=True is set, a full and de...

Django • Debugging

Consider Writing More Documentation, Tests, Logging and Assertions Instead of Using a Debugger

Debugging takes time and effort. Instead of chasing bugs with a debugger, consider spending more time on making your code better by: Write and run Tests. Python and Django have great builtin testing frameworks - that can be used to test your code much faster than manually with a debugger. Writ...

Django • Debugging

Sample server code

constexpr const size_t addressSize = sizeof(sockaddr_in); constexpr const uint16_t defaultPort = 80; // The port you want to use int serverSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); sockaddr_in serverAddress, clientAddress; memset(&serverAddress, 0, addressSize); serverAddress....

sockets • C++ Sockets

Displaying current angular2 version used in your project

To display current version, we can use VERSION from @angular/core package. import { Component, VERSION } from '@angular/core'; @Component({ selector: 'my-app', template: `<h1>Hello {{name}}</h1> <h2>Current Version: {{ver}}</h2> `, }) export class AppCompone...

Angular 2 • Commonly built-in directives and services

New Java SE 7 programming language features

Binary Literals: The integral types (byte, short, int, and long) can also be expressed using the binary number system. To specify a binary literal, add the prefix 0b or 0B to the number. Strings in switch Statements: You can use a String object in the expression of a switch statement The try-wit...

Java Language • Java SE 7 Features

New Java SE 8 programming language features

Lambda Expressions, a new language feature, has been introduced in this release. They enable you to treat functionality as a method argument, or code as data. Lambda expressions let you express instances of single-method interfaces (referred to as functional interfaces) more compactly. Method r...

Java Language • Java SE 8 Features

Nested if()...else VS if()..else Ladder

Nested if()...else statements take more execution time (they are slower) in comparison to an if()...else ladder because the nested if()...else statements check all the inner conditional statements once the outer conditional if() statement is satisfied, whereas the if()..else ladder will stop condit...

C Language • Selection Statements

Defining the document class

The very first line in each of your LaTeX programs should do this. It should follow the form \documentclass{...}. What you put within the curly braces is very important. Some document classes give you extra commands to use, others use a different format, and all have specific parameters you can inp...

latex • Document classes

Investigating where your DTU's go

If you want to investigate why you are maxing out your DTUs, add other metrics to the performance graph to see which metric is dominiationg your DTU usage. In this example, the DTU usage is clearly dominiated by the CPU usage

sql-azure • Database Transaction Units (DTUs)

Custom Camera Control - Mouse-based Sliding

Here's an example of a custom camera controller. This reads the position of the mouse within the client window, and then slides the camera around as if it were following the mouse on the window. index.html <html> <head> <title>Three.js Custom Mouse Camera Control Ex...

three.js • Camera Controls in Three.js

Discarding slow/outdated rest calls

A common usecase is to discard certain rest-calls, that are not needed any more after certain user-inputs. The most prominent example would be, when a user uses some search-function, makes a request, makes another request and for some reason the first request arrives after the second request and the...

rxjs • Common recipes

Clear derived data with hotkey

In the same way as in Open Terminal in current Xcode project folder example, you can add clear of derived data folder with hotkey. Create custom behavior (follow the steps in Open Terminal in current Xcode project folder). But use another script. Script text: #!/bin/bash rm -rf $HOME"/Lib...

Xcode • Customizing Xcode IDE

Locate a file on your system

Using bash you can easily locate a file with the locate command. For example say you are looking for the file mykey.pem: locate mykey.pem Sometimes files have strange names for example you might have a file like random7897_mykey_0fidw.pem. Let's say you're looking for this file but you only reme...

GNU/Linux • Shell

Decimal Integer literals

Integer literals provide values that can be used where you need a byte, short, int, long or char instance. (This example focuses on the simple decimal forms. Other examples explain how to literals in octal, hexadecimal and binary, and the use of underscores to improve readability.) Ordinary integ...

Java Language • Literals

Canvas Serilization

<canvas id = "canvas" height='400' width='500'></canvas> var canvas = new fabric.Canvas(document.getElementById('canvas')); console.log(JSON.stringify(canvas)); // '{"objects":[],"background":""}' canvas.add(new fabric.Rect({ left: 10, ...

fabricjs • FabricJS canvas Serialization

Using Packages to create classes with the same name

First Test.class: package foo.bar public class Test { } Also Test.class in another package package foo.bar.baz public class Test { } The above is fine because the two classes exist in different packages.

Java Language • Packages

Using Package Protected Scope

In Java if you don't provide an access modifier the default scope for variables is package-protected level. This means that classes can access the variables of other classes within the same package as if those variables were publicly available. package foo.bar public class ExampleClass { do...

Java Language • Packages

NSInvocation Objective-C

Refer to this original Post by e.James According to Apple's NSInvocation class reference: An NSInvocation is an Objective-C message rendered static, that is, it is an action turned into an object. And, in a little more detail: The concept of messages is central to the objective-c philosophy....

iOS • NSInvocation

Installation or Setup

jQuery plugins are typically installed via NPM or Yarn (if hosted there), or referencing an external script file containing the plugin, whether from a relative directory or a CDN. <script type="text/javascript" src="/path/to/plugin.jquery.js"></script>

jquery-plugins • Getting started with jquery-plugins

Objective-C Example

First declare a property like this in the ViewController @property (nonatomic) UIRefreshControl *refreshControl; Later in the viewDidLoad() set up the refreshControl as given below: self.refreshControl = [[UIRefreshControl alloc]init]; [self.tableView addSubview:self.refreshControl]; [self.re...

iOS • UIRefreshControl TableView