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The ng-required adds or removes the required validation attribute on an element, which in turn will enable and disable the require validation key for the input. It is used to optionally define if an input element is required to have a non-empty value. The directive is helpful when designing validat...

// Example of raw dynamic size array. It's generally better to use std::vector. #include <algorithm> // std::sort #include <iostream> using namespace std; auto int_from( istream& in ) -> int { int x; in >> x; return x; } auto main() -> int { ...

// A fixed size raw array matrix (that is, a 2D raw array). #include <iostream> #include <iomanip> using namespace std; auto main() -> int { int const n_rows = 3; int const n_cols = 7; int const m[n_rows][n_cols] = // A raw array matrix. ...

CanCan is a a popular authorization library for Ruby on Rails which restricts user access to specific resources. The latest gem (CanCanCan) is a continuation of the dead project CanCan. Permissions are defined in the Ability class and can be used from controllers, views, helpers, or any other place...

Some formats can take additional parameters, such as the width of the formatted string, or the alignment: >>> '{:.>10}'.format('foo') '.......foo' Those can also be provided as parameters to format by nesting more {} inside the {}: >>> '{:.>{}}'.format('foo', 10) '.......

<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"> <line x1="10" y1="10" x2="100" y2="100" stroke="red" stroke-width="10" /> <line x1="100" y1="10&...

The aar file doesn't contain the transitive dependencies and doesn't have a pom file which describes the dependencies used by the library. It means that, if you are importing a aar file using a flatDir repo you have to specify the dependencies also in your project. You should use a maven repositor...

HTML <div class="wrap"> <img src="http://lorempixel.com/400/200/" /> </div> CSS .wrap { height: 50px;/* max image height */ width: 100px; border: 1px solid blue; text-align: center; } .wrap:before { content:""; di...

A Button directive which accepts an @Input() to specify a click limit until the button gets disabled. The parent component can listen to an event which will be emitted when the click limit is reached via @Output: import { Component, Input, Output, EventEmitter } from '@angular/core'; @Component(...

The function angular.isDefined tests a value if it is defined angular.isDefined(someValue) This is the equivalent of performing value !== undefined; // will evaluate to true is value is defined Examples angular.isDefined(42) // true angular.isDefined([1, 2]) // true angular.isDefined(un...

This code makes sure that all nested containers are always the same height. This is done by assuring that all nested elements are the same height as the containing parrent div. See working example: https://jsfiddle.net/3wwh7ewp/ This effect is achieved due to the property align-items being set to...

A custom control does not have to limit itself to trivial things like primitives; it can edit more interesting things. Here we present two types of custom controls, one for editing persons and one for editing addresses. The address control is used to edit the person's address. An example of usage wo...

Mongoid allows Embedded Associations: One-to-one: embeds_one / embedded_in One-to-many: embeds_many / embedded_in To add an association (lets say the User embeds_many addresses), add this to your User file: embeds_many :addresses and this to your Address model file: embedded_in :user ...

And, of course, you can mix these approaches, and use both packages and imports along side your application specific code. A mix-mode structure is most common in three situations: a franken-app, which is just sort of pulling a bit from here-and-there without any overall strategy; an app that's bei...

Sometimes you will have a grid of subplots, and you want to have a single legend that describes all the lines for each of the subplots as in the following image. In order to do this, you will need to create a global legend for the figure instead of creating a legend at the axes level (which wil...

Deferred function calls serve a similar purpose to things like finally blocks in languages like Java: they ensure that some function will be executed when the outer function returns, regardless of if an error occurred or which return statement was hit in cases with multiple returns. This is useful f...

When adding content from sources outside your domain, or from the local file system the canvas is marked as tainted. Attempt to access the pixel data, or convert to a dataURL will throw a security error. vr image = new Image(); image.src = "file://myLocalImage.png"; image.onload = funct...

A pointer to base class can be converted to a pointer to derived class using static_cast. static_cast does not do any run-time checking and can lead to undefined behaviour when the pointer does not actually point to the desired type. struct Base {}; struct Derived : Base {}; Derived d; Base* p1 ...

Say you want to print variables in a 3 character column. Note: doubling { and } escapes them. s = """ pad {{:3}} :{a:3}: truncate {{:.3}} :{e:.3}: combined {{:>3.3}} :{a:>3.3}: {{:3.3}} :{a:3.3}: {{:3.3}} :{c:3...

We can omit the argument in the call if that argument is an Optional Argument Every Optional Argument has its own default value It will take default value if we do not supply the value A default value of a Optional Argument must be a Constant expression. Must be a value type such as enum or s...