ruby facets

Brief explanation of the scope of Ruby Object-Oriented Programming and ruby Object-Oriented Programming Scope Ruby does not have nested scopes (internal scopes, which can be viewed as external scopes). Their scopes are completely separated. Once a new scope is entered, the original binding will be replaced with a new binding group. The program will close the prev

Ruby captures web images and ruby captures images. Some time ago, I saw a lot of scripts written by my sister, and I wrote one myself. Module CommonHelper require 'nokogiri 'require 'open-uri 'def down_load_xmz site_url = "http://www.xxx.com" for index_page in 1 .. 141 doc_html = Nokogiri: HTML (open (site_url + '/share/comment-page-' + index_page.to_s) doc_html.css ("# comments p img "). each do | item_i

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 third-party PUSH Service Platform. You can use its APIs to easily push messages in real time! Browser compatibility: Go

Ruby concise learning notes (2): class inheritance, attributes, class variables, and ruby learning notes 1. How to declare a subclassCopy codeThe Code is as follows:Class Treasure In this way, the property names and descriptions of Thing classes are inherited by Treasure. 2. What are the parameters used to pass in the initialize method of the parent class in the following three methods?Copy codeThe Code is

Ruby Plus is a site offering free Ruby and rails related screencasts recorded by Bala paranj, much in the same vein as Ryan Bates 'railscasts. the screencasts are generally similar in length and overall format to those from railscasts. so far there are 29 episodes you can download. The first twelve screencasts in the archive (for which you have to register to download, alas) were exclusively

A summary of some common file operations in Ruby and a summary of ruby operations A lot of Ruby beginners need to learn. Now we are trying to use Ruby to write a script. Many file-related operations are used, which are sorted in stages here. This facilitates subsequent searches. Whether the file or directory exists

Collections writing guide in Ruby and Ruby collections writing guide Preference array and the literal representation of Hash (unless you need to pass parameters to their constructor ). # bad arr = Array.new hash = Hash.new # good arr = [] hash = {} When you need an array with elements of words (no spaces or special characters), you always use % w to define a string array. Apply this rule to only two

Installation will not say, the official website has, but today released ruby2.3, so updateEnter the. Rbenv directory, perform a git pull update, but update rbenv, execute rbenv install-l and do not have the latest 2.3.0 release version.Then I looked at the git repository for the Ruby-build plugin, with 2.3 code. Suspect this also to be updated, so.Go to the. Rbenv/plugins/ruby-build directory and execute gi

Ruby parsing JSONRuby Parsing JSON Example: JSON = ' ["A", "B", "C"] ' puts "Unsafe #{unsafe_json (JSON). Inspect}" #输出Unsafe ["A", "B", "C"] Ruby parses JSON to parse the above JSON string into array. Such a method is not safe, for example: JSON = ' puts ' Danger'll Robinson ' puts ' Unsafe #{unsafe_json (JSON). Inspect} " And what should we export? Unfortunately, there is

GitHub advocates a summary of Ruby coding styles, while github advocates ruby code. Source code layout: 1. All source files are UTF-8 encoded2. indent with two spaces3. Use Unix-style line breaks (\ n) and windows (\ r \ n ). You can use git config -- global core. autocrlf true to prevent the generation of windows-style line breaks.4. After ',', ';', add spaces before and after the operator (except for expo

Common Ruby file operation code instances and ruby code instances # Create a 222. rb file and the input character File = file. open ("222.rb"," w + ") file. puts "123 \ nwadwa \ n12124124 \ ndwdw" file. close # output 222. rb content File. open ("222.rb"," r + ") do | file | while line = file. getsputs lineendend # directly use IO to operate the file IO. foreach ("222.rb") do | line | puts line if line = ~

Ruby-implemented file self-deletion code sharing, ruby-implemented code sharing Because the File Deletion mechanism in windows is different from that in unix like, so does not guarantee that the following code can be used in windows. Which of the following kids shoes can help me test it in windows! Copy codeThe Code is as follows:#! /Usr/bin/ruby 5. times do |

1. Auxiliary methods2. StringEnter "IRB" into the ruby command-line development environment, and the controller starts by executing "rails console" on the command line.(1) String connection>>"foo"+"bar"="foobar" (2) Interpolation by special syntax #{}>>first_name="Amy" ="Amy">>" #{first_name} Sun"+"Amy Sun "(3) The difference between a single-quote string and a double-quote string: Single-quote strings they really are literal values, contain only the

When I started my ruby journey, I wrote my study notes for people with other OO language experiences. Let's take a look at the magic ruby. The first sample! First meeting. # ! /Usr/bin/ENV Ruby Class MegagreeterAttr_accessor: names # Create the object Def Initialize (names = " World " )@ Names = NamesEnd # Say hi

Explain the code block object Proc in Ruby, and explain the ruby object proc. Proc object Proc is a block conversion object. There are four methods to create a Proc: Sample Code # Method 1 inc = Proc. new {| x + 1} inc. call (2) #=> 3 # method 2 inc = lambda {| x + 1} inc. call (2) #=> 3 # method 3 inc =-> (x) {x + 1} inc. call (2) #=> 3 # Method 4 inc = proc {| x + 1} inc. call (2) # => 3 In addition to th

Various sorting algorithms implemented by Ruby and Ruby Time Complexity: Average (n ^ 2) Bubble sortCopy codeThe Code is as follows:Def bubble_sort ()(A. size-2). downto (0) do | I |(0.. I). each do | j |A [j], a [j + 1] = a [j + 1], a [j] if a [j]> a [j + 1]EndEndReturnEnd Selection sortCopy codeThe Code is as follows:Def selection_sort ()B = []A. size. times do | I |Min = a. minB A. delete_at (a. index (m

Class methods and class extensions in Ruby object-oriented programming, ruby Object-Oriented Programming Class Method The essence of a class method is a single-piece method that lives in a single-piece class of this class. Three methods are defined: # Method 1 def MyClass. a_class_method; end # method 2 class MyClass def self. anther_class_method; endend # method 3 * class MyClass class The third method in

Ruby-based optimal binary search tree algorithm and ruby-based optimal binary search algorithm The pseudo code in the introduction to algorithms is rewritten, plus the constructor for the solution of the first question in the Introduction Class Exercises.Copy codeThe Code is as follows:# Encoding: UTF-8= BeginAuthor: xu jinDate: Nov 11,201 2Optimal Binary Search TreeTo find by using EditDistance algorithmRe

Comparison of class variables and instance variables in Ruby, ruby class variable instances 1. The class variable name starts with @. A Class variable is shared by all instance objects of the class. The instance variable name starts with @, and each instance object has its own different instance variables; 2. class variables must be initialized before use; otherwise, an error is reported during use. If the

Summary of loop statements in ruby and summary of ruby loop statements While (when ...) Loop 　 　 While Condition Statement 1; Statement 2; statement... End Single Row while LOOP (Statement 1; Statement 2; statement... ) While Condition Until (...) Loop Until condition = while not (condition) For... In Loop 　 　 For variable in obj