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If you'd like to quickly test if an ability class is giving the correct permissions, you can initialize an ability in the console or on another context with the rails environment loaded, just pass an user instance to test against: test_ability = Ability.new(User.first) test_ability.can?(:show, Pos...

A UserForm is a class module with a designer and a default instance. The designer can be accessed by pressing Shift+F7 while viewing the code-behind, and the code-behind can be accessed by pressing F7 while viewing the designer. Work with a new instance every time. Being a class module, a form i...

import groovy.json.JsonSlurper; def jsonSlurper = new JsonSlurper() def obj = jsonSlurper.parseText('{ "foo": "bar", "baz": [1] }') assert obj.foo == 'bar' assert obj.baz == [1]

import groovy.json.JsonOutput; def json = JsonOutput.toJson([foo: 'bar', baz: [1]]) assert json == '{"foo":"bar","baz":[1]}' In addition to maps, lists and primitives groovy.json.JsonOutput also supports a POJOs serialitzation: import groovy.json.JsonOutput; ...

import groovy.json.JsonOutput; def json = JsonOutput.toJson([foo: 'bar', baz: [1]]) assert json == '{"foo":"bar","baz":[1]}' def pretty = JsonOutput.prettyPrint(json) assert pretty == '''{ "foo": "bar", "baz": [ ...

From dataframe: mtrdd <- createDataFrame(sqlContext, mtcars) From csv: For csv's, you need to add the csv package to the environment before initiating the Spark context: Sys.setenv('SPARKR_SUBMIT_ARGS'='"--packages" "com.databricks:spark-csv_2.10:1.4.0" "sparkr-shel...

Installation via Composer The easiest way to install the Incubator is by using Composer. Install Composer and create a new composer.json file in the root of your project. |-- app |-- public | `-- index.php |-- vendor |-- composer.json Add the following content to the composer.json file. ...

This is an example of a simple GET API call wrapped in a promise to take advantage of its asynchronous functionality. var get = function(path) { return new Promise(function(resolve, reject) { let request = new XMLHttpRequest(); request.open('GET', path); request.onload = resolve; ...

Use list() to quick assign a list of variable values into an array. See also compact() // Assigns to $a, $b and $c the values of their respective array elements in $array with keys numbered from zero list($a, $b, $c) = $array; With PHP 7.1 (currently in beta) you will be able to use s...

To create a custom standalone Gradle plug-in using java (you can also use Groovy) you have to create a structure like this: plugin |-- build.gradle |-- settings.gradle |-- src |-- main | |-- java | |-- resources | |-- META-INF | |-- gradle-plugins ...

Foreign keys enables you to define relationship between two tables. One (parent) table need to have primary key that uniquely identifies rows in the table. Other (child) table can have value of the primary key from the parent in one of the columns. FOREIGN KEY REFERENCES constraint ensures that valu...

FOREIGN KEY constraint can be added on existing tables that are still not in relationship. Imagine that we have Company and Employee tables where Employee table CompanyId column but don't have foreign key relationship. ALTER TABLE statement enables you to add foreign key constraint on an existing c...

FOREIGN KEY columns with constraint can be added on existing tables that are still not in relationship. Imagine that we have Company and Employee tables where Employee table don't have CompanyId column. ALTER TABLE statement enables you to add new column with foreign key constraint that references ...

sys.foreignkeys system view returns information about all foreign key relationships in database: select name, OBJECT_NAME(referenced_object_id) as [parent table], OBJECT_NAME(parent_object_id) as [child table], delete_referential_action_desc, update_referential_action_desc from sys.foreign...

Abstraction levels help determine when to split things up. Abstraction is achieved by implementing functionality with increasingly detailed code. The entry point of a macro should be a small procedure with a high abstraction level that makes it easy to grasp at a glance what's going on: Public Sub...

Detailed instructions on getting deep-learning framework set up or installed. Most frameworks supports interfaces in several languages: Caffe (C++, Python, Matlab) Tensorflow (C++, Python) Theano, Theano wrappers (Keras, Lasagne) (Python) Torch (Lua) Matconvnet (Matlab) Every framework i...

After installing a Java SDK, it is advisable to check that it is ready to use. You can do this by running these two commands, using your normal user account: $ java -version $ javac -version These commands print out the version information for the JRE and JDK (respectively) that are on your sh...

Introduction: Swagger is a set of rules/specifications for a format describing REST APIs. It provides a powerful and actively developed ecosystem of tools around this formal specification like code generators and editors. The best part of Swagger is that the documentation of methods, parameters, an...

If you're using an icon to add some extra decoration or branding, it does not need to be announced to users as they are navigating your site or app aurally. Additionally, if you're using an icon to visually re-emphasize or add styling to content already present in your HTML, it does not need to be r...

PM> uninstall-Package EntityFramework -Version 6.1.2