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RVM is a great tool to manage your ruby versions and set up your working environment. Assuming you already have RVM installed, to get the latest version of ruby, which is needed for these examples, open a terminal and run: $ rvm get stable $ rvm install ruby --latest Check your ruby version by...

All collection objects contain a map method that takes a Function as an argument, which must take a single argument. This returns an Iterable backed by the collection. When the Iterable is iterated, each step calls the function with a new element of the collection, and the result of the call becomes...

You will often need to access instances of classes from the framework itself (like the WSClient, or the Configuration). You can inject them in your own classes : class ComplexService @Inject()( configuration: Configuration, wsClient: WSClient, applicationLifecycle: ApplicationLifecycle, ...

Basic usage of dependency injection is done by the annotations. When you need to tweak things a little bit, you need custom code to further specify how you want some classes to be instantiated and injected. This code goes in what is called a Module. import com.google.inject.AbstractModule // Pla...

PBKDF2 ("Password-Based Key Derivation Function 2") is one of the recommended hash-functions for password-hashing. It is part of rfc-2898. .NET's Rfc2898DeriveBytes-Class is based upon HMACSHA1. using System.Security.Cryptography; ... public const int SALT_SIZE = 24; //...

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...

Abilities are defined in the Ability class using can and cannot methods. Consider the following commented example for basic reference: class Ability include CanCan::Ability def initialize(user) # for any visitor or user can :read, Article if user if user.admin? ...

Once the number of abilities definitions start to grow in number, it becomes more and more difficult to handle the Ability file. The first strategy to handle these issue is to move abilities into meaningful methods, as per this example: class Ability include CanCan::Ability def initialize(...

Build numberDescription15.0.4623.1001June 201415.0.4631.1001July 201415.0.4641.1001August 201415.0.4649.1001September 201415.0.4659.1001October 201415.0.4667.1000November 201415.0.4675.1000December 201415.0.4693.1001February 201515.0.4701.1001March 201515.0.4711.1000April 2015 (SP1 REQ)15.0.4719.100...

Although it's bad practice, it's possible to add multiple return statements in a exception handling block: public static int returnTest(int number){ try{ if(number%2 == 0) throw new Exception("Exception thrown"); else return x; } catch(Exception e){ ...

When you implement java.io.Serializable interface to make a class serializable, the compiler looks for a static final field named serialVersionUID of type long. If the class doesn't have this field declared explicitly then the compiler will create one such field and assign it with a value which come...

Download the Atlassian conversion utility here. This utility requires Java, so please ensure that you have the Java Runtime Environment JRE installed on the machine you plan to do the conversion. Use the command java -jar svn-migration-scripts.jar verify to check if your machine is missing any of t...

The macro WITH-INPUT-FROM-STRING can be used to make a stream from a string. (with-input-from-string (str "Foobar") (loop for i from 0 for char = (read-char str nil nil) while char do (format t "~d: ~a~%" i char))) ; 0: F ; 1: o ; 2: o ; 3: b ;...

The macro WITH-OUTPUT-TO-STRING can be used to create a string output stream, and return the resulting string at the end. (with-output-to-string (str) (write-line "Foobar!" str) (write-string "Barfoo!" str)) ;=> "Foobar! ; Barfoo!" The same can be done ...

A file can be opened for reading as a stream using WITH-OPEN-FILE macro. (with-open-file (file #P"test.file") (loop for i from 0 for line = (read-line file nil nil) while line do (format t "~d: ~a~%" i line))) ; 0: Foobar ; 1: Barfoo ; 2: Quuxbar...

A file can be opened for writing as a stream using WITH-OPEN-FILE macro. (with-open-file (file #P"test.file" :direction :output :if-exists :append :if-does-not-exist :create) (dolist (line '("Foobar" &q...

Installing Tcl 8.6.4 on Windows : The easiest way to get Tcl on a windows machine is to install the ActiveTcl distribution from ActiveState. Navigate to www.activestate.com and follow the links to download the Free Community Edition of ActiveTcl for Windows (choose 32/64 bit version app...

Method stopLoading() stops the current loading process of the webview. Swift webview.stopLoading() Objective-C [webview stopLoading];

Don't put comments after mappings, it will break things. Use :map <F6> to see what is mapped to <F6> and in which mode. Use :verbose map <F6> to also see where it was last mapped. :map and :map! are too generic. Use :n[nore]map for normal mode mappings, :i[nore]map for insert ...

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) '.......