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A has_many :through association is often used to set up a many-to-many connection with another model. This association indicates that the declaring model can be matched with zero or more instances of another model by proceeding through a third model. For example, consider a medical practice where p...

A has_one :through association sets up a one-to-one connection with another model. This association indicates that the declaring model can be matched with one instance of another model by proceeding through a third model. For example, if each supplier has one account, and each account is associated...

A has_and_belongs_to_many association creates a direct many-to-many connection with another model, with no intervening model. For example, if your application includes assemblies and parts, with each assembly having many parts and each part appearing in many assemblies, you could declare the models...

We can check the status of migrations by running 3.05.0 rake db:migrate:status 5.0 rails db:migrate:status The output will look like this: Status Migration ID Migration Name -------------------------------------------------- up 20140711185212 Create documentation pages up ...

In order to compile and run SystemVerilog code a tool called a simulator is needed. Most commonly, commercial tools from one of the Big Three EDA companies is used: Cadence Incisive Mentor Graphics QuestaSim Synopsys VCS Other EDA vendors also provide simulators: Aldec Riviera-PRO Xilinx...

An easy way to clone an object is by implementing a copy constructor. public class Sheep { private String name; private int weight; public Sheep(String name, int weight) { this.name = name; this.weight = weight; } // copy constructor // copies...

Cloning an object by implementing the Cloneable interface. public class Sheep implements Cloneable { private String name; private int weight; public Sheep(String name, int weight) { this.name = name; this.weight = weight; } @Override public Ob...

“Fat Model, Skinny Controller” refers to how the M and C parts of MVC ideally work together. Namely, any non-response-related logic should go in the model, ideally in a nice, testable method. Meanwhile, the “skinny” controller is simply a nice interface between the view and model. In practice, this...

Rails provides a lot of generators, for controllers too of course. You can generate a new controller by running this command in your app folder rails generate controller NAME [action action] [options] Note: You can also use rails g alias to invoke rails generate For example, to generate a cont...

Configuration files for rails can be found in config/environments/. By default rails has 3 environments, development, production and test. By editing each file you are editing the configuration for that environment only. Rails also has a configuration file in config/application.rb. This is a common...

Database configuration of a rails project lies in a file config/database.yml. If you create a project using rails new command and don't specify a database engine to be used then rails uses sqlite as the default database. A typical database.yml file with default configuration will look similar to fol...

You can get a Model class from a Controller name this way (context is Controller class): class MyModelController < ActionController::Base # Returns corresponding model class for this controller # @return [ActiveRecord::Base] def corresponding_model_class # ... add some validation...

In the case of a multi-project gradle build, you may sometimes need to depend on another project in your build. To accomplish this, you'd enter the following in your project's dependencies: dependencies { compile project(':OtherProject') } Where ':OtherProject' is the gradle path for the p...

Consumable Managed Products are products that can be bought multiple times such as in-game currency, game lives, power-ups, etc. In this example, we are going to implement 4 different consumable managed products "item1", "item2", "item3", "item4". Steps in...

console.count([obj]) places a counter on the object's value provided as argument. Each time this method is invoked, the counter is increased (with the exception of the empty string ''). A label together with a number is displayed in the debugging console according to the following format: [label]: ...

Debug.log's second argument is always returned, so you could write code like the following and it would just work: update : Msg -> Model -> (Model, Cmd Msg) update msg model = case Debug.log "The Message" msg of Something -> ... Replacing case msg o...

There are a few libraries for unit testing in Common Lisp FiveAM Prove, with a few unique features like extensive test reporters, colored output, report of test duration and asdf integration. Lisp-Unit2, similar to JUnit Fiasco, focusing on providing a good testing experience from the REPL. Su...

The following examples can be tested on https://ellie-app.com/m9vmQ8NcMc/0. import Html exposing (..) import Json.Decode payload = """ [ { "bark": true, "tag": "dog", "name": "Zap", "playful": true } , { "w...

Content scripts can be declared in manifest.json to be always injected into pages that match a set of URL patterns. Minimal example "content_scripts" : [ { "js": ["content.js"], "css": ["content.css"] "matches": [&quot...

If, instead of always having a content script injected based on the URL, you want to directly control when a content script is injected, you can use Programmatic Injection. Minimal example JavaScript chrome.tabs.executeScript({file: "content.js"}); CSS chrome.tabs.insert...