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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

Matrix concatenation algorithm implemented by Ruby and ruby matrix concatenation Dynamic Planning solves the problem of matrix concatenation, generates matrix sequences randomly, and outputs results in the form of (A1 (A2A3) (A4A5. Code: #encoding: utf-8=beginauthor: xu jin, 4100213date: Oct 28, 2012MatrixChainto find an optimum order by using MatrixChain algorithmexample output:The given array is:[30, 35,

Simple implementation of the Bubble Sorting Algorithm and Ruby version, and the Bubble Sorting Algorithm ruby Algorithm principle: Compares adjacent elements. If the first is bigger than the second, exchange the two of them.Perform the same operation on each adjacent element, from the first to the last. At this point, the final element should be the largest number.Repeat the preceding steps for all elements

machineInitialization completeStart the environment execution vagrant Halt shutdown environment by executing vagrant up in the appropriate directory when usedOther points of attentionAfter successful initialization, a configuration file named Vagrantfile is generated in the appropriate directory, which can be set for network, memory size, and other content.This article is from the "7692323" blog, please be sure to keep this source http://7702323.blog.51cto.com/7692323/1596334Build a

A few Ruby tips and Ruby tips Sequential call of code blocksCopy codeThe Code is as follows:Def touch_downYield [3, 7]Puts "touchdown! "EndTouch_down do | (first_down, second_down) |Puts "# {first_down} yards on the run"Puts "# {second_down} yards passed"End=> "3 yards on the run"=> "7 yards passed"=> "Touchdown! " It mainly refers to the use of array in block Retrieve elements from arrayCopy codeThe Code i

Example of the use of hundreds of semicolons and literal values in Ruby: ruby percent Use % () (abbreviated as % Q) for a single line string that requires interpolation and embedding double quotation marks ). Multi-line string, preferably heredocs. # bad (no interpolation needed) %( Do not use % q for strings without 'and. Unless many characters need to be escaped, the normal string is more readable.

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

entities are destroyed Delete_all: All associated entities are deleted directly from the database, unrecoverable nullify: foreign keys are Set to NULL, unrecoverable restrict_with_exception: Throw exception hint Restrict_with_error: Throw error prompt 5, Foreign_key: Define column name for foreign Key 6, inverse_of : Indicates the inverse associated entity 7, Primary_key: Indicates the associated item ID 8, through: Indicates that a many-to-many relationship uses a third-party entity 9, validat

version that follows the Rbenv install command should correspond to the version of Ruby that you want to install, such as the version that may be installed with the corresponding patch number (for example: 1.9.3-p223), which should also be written here.2. Install the necessary components because we generally use bundler to manage the gems required for a project, we need to install bundler here.Considering the speed of the domestic connection to