Ruby

A constant begins with a capital letter. It should be assigned up to one time. In the current version of Ruby, the re-assignment of constants produces only warnings rather than errors (the Non-ansi version of EVAL.RB does not report this warning)

First, the method Ruby's method definition allows you to set a default value for a parameter, but you cannot have a parameter without a default value after an argument with a default value (Allow * and &), meaning that the following method

Get enumeration capabilities from each The Class you want to enumerate has to have a each method, and its job is to yield the project to a code block, one at a time. Each does things differently on different classes, such as on an array, each

Rack is a framework between the Ruby server and the rack application, Rails,sinatra is built on rack and belongs to the rack application. Rack provides a standard interface for interacting with the server. The standard rack program is an object

A module is similar to a class, and it can also be said to be "a class that cannot be instantiated." Because class classes are subclasses of the module class, it might be better to say "class = module + instantiation capability." What is the

The best way to prove the scalability of rails is to look at an application that actually scales effectively. Here we look at the performance problems encountered by three real-world applications and how they solve these problems. 37signals

In this chapter I have met the C-language struct data, which is the custom data structure. Like what:struct Edge{int u;int V;int W;};The topic gives a set of data that is stored with the edge. You need to sort by the W size. I didn't know how to do

problem: when using the mesh structure test in Ruby memory system, the following error occurred:Traceback (most recent call Last): File"", Line 1,inch File"/home/fandroid/gem5/src/python/m5/main.py", Line 388,inchMain T = T.tb_next

1. Check whether Ruby-debug-Ide is installed. $ Gem list 2. If not, install ruby-debug-ide $ Gem install ruby-debug-ide 3. Open your project in Aptana Studio 3 and enable the debug server: app Explorer-> gear drop-down menu-> debug Server 4.set

Like most object-oriented languages, Ruby classes allow class variables and methods to be defined. A class variable allows a single variable to be shared among all instances of a class. In Ruby, two @ signs are used to indicate class variables. For

Reference: http://rubyer.me/blog/485 Http://sunnyshuhai.iteye.com/blog/286970 In Ruby, global variables, instance variables, class variables, and symbol are often very different from other languages such as Java and are easy to mix up.First, there

How to configure the Ruby development environment in CentOS 7, centosruby This article will share with you a tutorial on how to configure the Ruby development environment in CentOS 7 for your reference. Here is a detailed introduction: Install Ruby 2

Ruby Web Real-Time Message backend server push technology --- GoEasy, ruby --- goeasy More and more projects require real-time message pushing and receiving. How can we use Ruby to achieve the most convenient? We recommend that you use GoEasy, a

A concise tutorial on Ruby and Ruby on Rails framework Environment setup, rubyrails Install Ruby and upgrade RubyGemsTip: During the installation process in Ubuntu, if a permission error is prompted, you can use sudo make and sudo make install. 1.

Example parsing: Implementation of observer mode in Ruby design mode development, and ruby Design Mode In general, the observer mode should be defined as follows: building a clean interface between the source of news that some object has changed and

Six Methods for executing Linux shell commands in Ruby: rubyshell In Ruby, executing shell commands is not surprising. Ruby provides about six methods for developers to implement. These methods are very simple. This article will introduce how to

Ruby implements the active mail push trigger program, and ruby implements mail triggering After receiving the email, the mail server pushes the notification program. Is there any way to achieve this? 1. Client polling2. The server actively pushes

An example of jQuery's problem in determining whether an element exists This is the case. During jQuery training recently, jQuery encountered a problem when determining whether the element exists. The question is as follows: add Id = rad4 after

Basic tutorial on Rack middleware in Ruby on Rails, railsrack Rack is a framework between the ruby server and the rack application. rails and sinatra are both built based on rack and belong to rack applications. Rack provides a standard interface

Getting started with image processing in Ruby on Rails, rubyrails Images can be said to be a vital part of any application. From social networks to a simple Bug tracker, images play an important role. However, managing images is not an easy task. It