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Specially useful for has_and_belongs_to_many relation, you can manually create a join table using the create_table method. Suppose you have two models Tags and Proyects, and you'd like to associate them using a has_and_belongs_to_many relation. You need a join table to associate instances of both c...

CSS styles for the credits label. Defaults to: credits: { style: { cursor: 'pointer', color: '#909090', fontSize: '10px' } },

Position configuration for the credits label. Supported properties are align, verticalAlign, x and y. Defaults to: credits: { position: { align: 'right', x: -10, verticalAlign: 'bottom', y: -5 } },

The DATEDIF function returns the difference between two date values, based on the interval specified. It is provided for compatibility with Lotus 1-2-3. The DATEDIF function cannot be found on the function list and autocomplete and screen tips are unavailable. Note: It is pronounced "date diff&...

Before C++17, having pointers with a value of nullptr commonly represented the absence of a value. This is a good solution for large objects that have been dynamically allocated and are already managed by pointers. However, this solution does not work well for small or primitive types such as int, w...

This illustrates that union members shares memory and that struct members does not share memory. #include <stdio.h> #include <string.h> union My_Union { int variable_1; int variable_2; }; struct My_Struct { int variable_1; int variable_2; }; int main (void) { ...

Assert.That(actual, Is.EqualTo(expected));

The bind method of every function allows you to create new version of that function with the context strictly bound to a specific object. It is specially useful to force a function to be called as a method of an object. var obj = { foo: 'bar' }; function foo() { return this.foo; } fooOb...

To create a custom template we first need to create php file in a theme directory. You can name it almost any way you want. For this example we will create example.php One and only thing we need to define inside our example.php, to be recognized by WordPress as a template, is template name. We do t...

Some attributes are directly accessible as properties of the element (e.g. alt, href, id, title and value). var a = document.querySelector("a"), url = a.href; Other attributes, including data-attributes can be accessed as follows: var a = document.querySelector("a"), ...

Values can be given names using let: # let a = 1;; val a : int = 1 You can use similar syntax to define a function. Just provide additional parameters for the arguments. # let add arg1 arg2 = arg1 + arg2;; val add : int -> int -> int = <fun> We can call it like this: # add 1...

Classes, structures, and enumerations can define subscripts, which are shortcuts for accessing the member elements of a collection, list, or sequence. Example struct DaysOfWeek { var days = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri"...

A defer statement in Go is simply a function call marked to be executed at a later time. Defer statement is an ordinary function call prefixed by the keyword defer. defer someFunction() A deferred function is executed once the function that contains the defer statement returns. Actual call to th...

Standard enumerations allow users to declare a useful name for a set of integers. The names are collectively referred to as enumerators. An enumeration and its associated enumerators are defined as follows: enum myEnum { enumName1, enumName2, }; An enumeration is a type, one which is...

If targeting Flash Player 11+, the built-in removeChildren method is the best way to remove all children: removeChildren(); //a start and end index can be passed For legacy applications, the same can be accomplished with a loop: while (numChildren > 0) { removeChildAt(0); }

// RawRepresentable has an associatedType RawValue. // For this struct, we will make the compiler infer the type // by implementing the rawValue variable with a type of String // // Compiler infers RawValue = String without needing typealias // struct NotificationName: RawRepresentable { ...

We define the type of boolean expressions whose atoms are identified by strings as type expr = | Atom of string | Not of expr | And of expr * expr | Or of expr * expr and can evaluate these expressions using an oracle : string -> bool giving the values of the atoms we find as follows: le...

final TextView mTextView = (TextView) findViewById(R.id.text); ... // Instantiate the RequestQueue. RequestQueue queue = Volley.newRequestQueue(this); String url ="http://www.google.com"; // Request a string response from the provided URL. StringRequest stringRequest = new String...

There are several additional attributes that the Volley NetworkImageView adds to the standard ImageView. However, these attributes can only be set in code. The following is an example of how to make an extension class that will pick up the attributes from your XML layout file and apply them to the N...

The C++ approach - new and delete In a language like C++, the application program is responsible for managing the memory used by dynamically allocated memory. When an object is created in the C++ heap using the new operator, there needs to be a corresponding use of the delete operator to dispose o...