install ruby

Four Methods for Equality judgment in Ruby and four methods for ruby equality judgment It has long been known that ruby has four equality judgment methods: "=", "=", and "equal ?" And "eql ?", It is used in common programs, but I feel that I lack a deep understanding of it. When I read some of the rails source code today, I cannot determine the meaning of one of

We strongly recommend that you use the following Online Learning Websites: http://tryruby.org: Ruby returns the last value in the method by default. To return multiple values, you can use an array. You can return a value by forcibly declaring return. The basic output method is to use puts (output line) and print (print directly ). The Basic Input Method is gets (read a row that contains '\ n' at the end of the row, which can be eliminated by cho

Basic Learning notes for Ruby metaprogramming and ruby learning notes Note 1:The Code contains variables, classes, and methods, collectively referred to as language construct ). # test.rbclass Greeting def initialize(text) @text = text end def welcome @text endendmy_obj = Greeting.new("hello")puts my_obj.classputs my_obj.class.instance_methods(false) #false means not inheritedputs my_obj.instance_variable

Assignment related operations in Ruby programming and ruby programming assignment In earlier versions of Ruby, the return value of the value assignment statement is the return value of the method that sets this attribute. In Ruby1.8, the value of the value assignment statement is always the value of the parameter, and the return value of the method is lost. class

Build RubyMine + Ruby On Rails + MySQL development environment in Windows I recently took over a mobile phone project. Some problems have been encountered during the environment setup process. We have recorded the problems in the following article and offered our solutions. Development Environment: Windows 2003; JetBrains RubyMine6.3.3 1. download the latest version of ruby(rubyinstaller-2.0.0-p598.exe, the

Global variable $ XX Object variable @ xx Local variable [A-Z] xx Constant [A-Z] xx Two pseudo variables self and nil:Self is actually a global variable pointing to the current object. The value of this variable is controlled by the interpreter and can only be read and cannot be modified.Nil is also a global variable controlled by the interpreter and cannot be assigned a value. 1. Global variable $ XXGlobal variables should be used with caution because their scope is script-level and can

I used to want to use Java for something similar. Today I see Ruby already has ----- Gem install Chardet-y ----- Require 'rubygems'Require 'universaldetector'Require 'net/http'Net: http. version_1_2Net: http. Start ('www .sina.com.cn ') {| HTTP |Data = http. Get ("/"). BodyP universaldetector: chardet (data)}It is a Python version transplant, and there is a confidence parameter. I tested several site

recently took over a Ruby Web project, and since it was not previously exposed to Ruby and related web development, and the document was missing, it was a bit of a detour to deploy the project .。Finally, we have successfully deployed the project by referring to several Ruby on rails development environment deployment and learning the relationship between Gem/bund

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 2.2 The Ruby version in th

Example of writing code for exception handling in Ruby, and ruby Exception Handling A single exception uses the fail keyword only when an exception is caught and thrown repeatedly (because you do not fail here, but are accurate and intentionally throw an exception ). begin fail 'Oops' rescue => error raise if error.message != 'Oops' end Do not specify an accurate RuntimeError for fail/raise. # bad

Tutorial on interrupt and return in Ruby programming and tutorial on ruby programming usage The use of the return, break, and next keywords involves the issue of jumping out of the scope. Their difference lies in the different scopes of different keywords jumping out, because there are code blocks, you need to pay special attention to them.ReturnCommon Methods Generally, the return statement is the same as

Example parsing for Hook methods in Ruby and ruby hook instance Parsing By using the Hook method, we can intervene in the life cycle of Ruby classes or modules, greatly improving programming flexibility.The following hook methods related to lifecycle are available: Classes and modules Class # inherited Module # include Module # prepended Module # extend_

Let's get back to our jukebox for a moment (remember the jukebox ?). At some point We'll be working on the code that handles the user interface-the buttons that people Press to select songs and control the jukebox. We'll need to associate actions Those buttons: press START and the music starts. It turns out that Ruby's blocks are A convenient way to do this. Let's start by assuming that the people who made Hardware implemented a Ruby extension that gi

1. Debug comment Print output debugRuby is an interpreted language, a script, and on Linux, scripts cannot be executed in three ways:1. Run the script with the interpreterInterpreter script FileThat is:Ruby script File2. Run the script directlyIn the script file, use the#! Script InterpreterDefine the script interpreter path, then grant the script execute permission, then run directly./script FileCan.3. Run the script inside the interpreter[Email protected]:/home/ywt/ror_tests/ruby_tests# irb