ruby singleton

The initial definition of the singleton pattern appears in design mode (Eddisonvis, 1994): "Guarantees that a class has only one instance, and provides a global access point to access it." ”Features: First, there can only be one instance of a class;The second is that it must create this instance on its own;Thirdly, it must provide this instance to the whole system on its own.First, the classic realizationusingSystem;namespacesingletonpattern{//Classic

Singleton and singleton) 1. Use Cases Stackorverflow Controls concurrent access to a shared resource. Access to the resource will be requested from multiple, disparate parts of the system. There can be only one object. From (http://stackoverflow.com/questions/228164/on-design-patterns-when-to-use-the-singleton) 2. Simple Mode Public class BaseSingle{Public

Meyers version in singleton mode and meyers version in singleton Mode View the Code directly: /* The Singleton mode ensures that a class has only one instance in a program and provides a global access point for accessing it in the program design, in many cases, make sure that one class has only one instance. For example, in the donepws system, only one window ma

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

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

Singleton The Code is as follows: Public class Singleton Usage: Public class User: Singleton Implementing the Singleton Pattern in C # Chinese Version

Secure Implementation of multi-threaded Singleton mode and multi-threaded Singleton Mode Multi-threaded Singleton mode. Through Dual locking and Spin processing, secure multi-threaded singleton and shared zone data access is achieved. Resource Access takes the form of simple waiting for processing, and std: bind is use

A Date and Time Processing tutorial in Ruby and a date Processing tutorial in ruby The Time class is used in Ruby to represent the date and Time. It is based on the system date and time provided by the operating system. This type may not represent the date before or after January 1. This tutorial will familiarize you with all important concepts of date and time.C

Analysis of Ruby source code layout and programming style, analysis of ruby source code Layout Use the UTF-8 as the source file encoding. Each indentation level uses two spaces (also known as soft tabs). Do not use hard tabs # bad - four spaces def some_method do_something end # good def some_method do_something end Use Unix-style line breaks. (* Users of BSD, Solaris, Linux, and OSX are covered

Ruby learning plan-(0) preface, ruby Preface Preface Currently, C, C ++, Java, Object-C, and Swift programming languages have been used. The most familiar language is oc. After all, it depends on him for dinner. It is only a beginner's path for other languages. Because he has been engaged in iPhone app development, recently, I wanted to develop a project by myself, but there was no backend, so I was so

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

your Ruby script. featuresFully object-oriented, in the Ruby language, anything is an object, including basic data types in other languages, such as integer variables without types, and ruby variables can hold any type of data. Everything has a value, whether it's a number or a logical expression or a statement. The Ruby