ruby facets

I have recently considered a lot of metaprogramming (metaprogramming) issues and would like to see more examples and explanations of this technology. For better or worse, Metaprogramming has entered the Ruby community and is a standard way to accomplish various tasks and simplify code. Since I can't find this kind of resources, I'm going to start writing some general Ruby technology articles. These may be u

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

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

Tutorial on creating and using hash in Ruby and ruby hash Hash is a set of key-value pairs similar to "employee" => "salary. Hash indexes are completed by any key of any object type, rather than an integer index. Others are similar to arrays. The hash traversal order by key or value seems random, and is generally not in the insertion order. If you try to access the hash using a key that does not exist, the

An example is provided to explain the regular expressions in Ruby and the regular expressions in ruby. A regular expression is a special character sequence that can help match or find other strings or strings. The pattern used maintains a special syntax. The regular expression text is a slash between a pattern or any separator % r is as follows:Syntax: Copy codeThe Code is as follows:/pattern//Pattern/im #

Ruby meta-programming summary, ruby Summary When I was asked such questions today, I used to think that this is a broad concept. Even if I have used these features, but I still don't know this is called "metaprogramming" until today when I was asked, I just had an epiphany, and then I made a small summary on the Internet with some of my actual metaprogramming. The so-called meta-programming in

For Ruby introduction, see: http://www.ruby-lang.org/zh_CN/about/ I. IRB Interactive Ruby help and consoleProgramIn Windows. You can directly execute Ruby in IRB.Code. For example: Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--> IRB (main ): 001 : 0 > " Hello World " => " Hello W

Enter the command line in ruby to compile sass (ruby) and rubysass Ruby(Or cmd) Enter the command line to compile sass as follows: (1) For example: first, create a total folder under drive F, such as the test folder, and then create folders such as html, images, js, and sass under the folder. (2) Create the sass file to be used in the sass folder. For example, co

I have always been very interested in Ruby on Rails. I want to see something that has been praised by many people, but I have been working on windows development, it is still a headache to build the development environment of Ruby on Rails, Which is why Ruby on rails has not been studied. I just saw InstantRails In javaeye, an All-In-One suite, which can help you