include vs extend in Ruby: Clear Rules, Real Patterns
Understand exactly how include and extend work in Ruby, with method lookup rules, common mistakes, and production patterns.
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Ruby
Ruby programming guides, Rails tips, and metaprogramming resources for developers of all levels.
Ruby Programming
Ruby programming guides, Rails tips, and metaprogramming resources for developers of all levels.
Ruby is a dynamic, interpreted, object-oriented language designed by Yukihiro “Matz” Matsumoto with the principle of “optimizing for developer happiness.” Its elegant syntax, powerful metaprogramming capabilities, and convention-over-configuration philosophy — best exemplified by Ruby on Rails — have made it a mainstay in web development since the mid-2000s.
Articles
- Active Support Concern
- ActiveRecord::Relation vs ActiveRecord Objects in Rails
- [alias and alias_method in Ruby](alias-and-alias-method-in-ruby/
- alias and alias_method
- [AOP Programming in Ruby](aop-programming/
- attr_checked in Metaprogramming Ruby
- attr_accessor, attr_reader, and attr_writer in Ruby
- Autoload in Rails
- Implementing a blank? Helper in Ruby
- Debugging Capistrano Deploy Failures
- Ruby class_attribute
- class_eval and instance_eval in Ruby
- Understanding class_eval, module_eval and instance_eval
- Class Instance Variables in Ruby
- Class Methods and Singleton Methods in Ruby
- Class Variables in Ruby
- Class Variables vs Class Instance Variables in Ruby
- class_variable, class_instance_variable, and class_attribute
- Using Class Variables for Counters in Ruby
- [Content Class Methods](content-class/
- How to Create a Gem For JavaScript and CSS Libraries
- define_attribute_methods in Rails
- Dynamic Dispatch in Ruby
- Equality and Comparison in Ruby
- Ruby: Strengths, Weaknesses, and When to Use It
- Hash vs Struct in Ruby
- include vs extend in Ruby
- include vs extend: Adding Methods to Classes and Objects
- instance_eval, instance_exec, class_eval, and module_eval
- Instance Methods in Ruby
- [Interface Inheritance vs Implementation Inheritance in Ruby and Go](interface-inheritance-vs-implementation-inheritance/
- Loops and Iteration in Ruby
- Rails mattr_accessor
- method_missing in Ruby
- Object-Oriented Programming in Ruby
- Ruby prepend vs include
- public, private, and protected Methods in Ruby
- [Rails Callbacks for Data Consistency](rails-use-callback-to-ensure-data-consistency-in-the-case-of-multiple-associated-models/
- Avoiding Duplicate HTML IDs in Rails Forms
- Ruby Args: Positional, Keyword, and Variable Arguments
- Essential Ruby Articles and Learning Resources
- Ruby Class Extension Pattern
- Understanding self in Ruby
- Sessions in Rails
- Shopping Cart Goods Update in Rails
- Singleton Methods and the Singleton Class in Ruby
- Constants and Namespaces in Ruby
- Dynamic Languages and Runtime Errors: Ruby’s Late Binding Risks
Ruby Args 参数处理：位置参数、关键字参数与可变参数
系统讲解 Ruby 参数机制：位置参数、默认值、可变参数、关键字参数、转发参数和常见坑位。
define_attribute_methods in Rails: Complete Guide to Dynamic Attribute Methods
A comprehensive guide to define_attribute_methods in Rails - generating attribute accessors, mutators, and query methods dynamically for ActiveRecord models.
Shopping Cart Goods Count Update in Rails(class variable)
Shopping Cart Goods Count Update in Rails(class variable)
Rails mattr_accessor详解
Rails mattr_accessor详解
Class Variables vs Class Instance Variables in Ruby
Understand the difference between class variables (@@var) and class instance variables (@var) in Ruby — how they behave with inheritance and when to use each.
Autoload in Rails: Complete Guide to Constant Autoloading
Understanding autoload in Rails - how Rails automatically loads constants and modules based on directory structure and naming conventions. Covers classic autoloader and Zeitwerk.
instance_eval, instance_exec, class_eval, and module_eval in Ruby
A complete guide to Ruby's context-switching methods — instance_eval, instance_exec, class_eval, and module_exec — with practical use cases and security considerations.
alias and alias_method in Ruby
Learn how to use alias and alias_method in Ruby — renaming methods, wrapping behavior, and the key differences between the two.
alias and alias_method in Ruby: Complete Guide
A comprehensive guide to using alias and alias_method in Ruby for method aliasing, metaprogramming, code reuse, and Rails patterns.
class variable and class instance variable and class_attribute in Ruby
class variable and class instance variable and class_attribute in Ruby
Content Class Methods
Content Class Methods
Thinking About ActiveRecord::Concern
Thinking About ActiveRecord::Concern
Constants and Namespaces in Ruby
A complete guide to Ruby constants — how constant lookup works, namespacing, the :: operator, and common pitfalls with nested classes.
Hash vs Struct in Ruby: When to Use Each
A complete guide to Ruby's Hash and Struct — their differences, use cases, and when Struct is the better choice for structured data.
AOP Programming in Ruby
Understanding Aspect-Oriented Programming (AOP) in Ruby - patterns, implementation, and use cases for separating cross-cutting concerns.
Ruby prepend vs include: Module Composition Guide
Learn how Ruby's prepend works, how it differs from include, and when to use each for module composition and method wrapping.
Essential Ruby Articles and Learning Resources
A curated collection of essential Ruby articles covering modules, metaprogramming, equality operators, and the Ruby object model.
Singleton Methods and the Singleton Class in Ruby
A complete guide to Ruby's singleton methods and singleton class — what they are, how they work, and how they underpin class methods and Ruby's object model.
Dynamic Dispatch in Ruby: send, public_send, and Method Objects
A complete guide to Ruby's dynamic dispatch — using send, public_send, and method objects to call methods dynamically, bypass visibility, and build flexible APIs.
attr_accessor, attr_reader, and attr_writer in Ruby
A complete guide to Ruby's attribute accessors — attr_accessor, attr_reader, and attr_writer — with examples, custom implementations, and best practices.
Using Class Variables for Counters and Shared State in Ruby
Practical patterns for using Ruby class variables as counters — with thread safety, inheritance considerations, and better alternatives.
method_missing in Ruby: Ghost Methods and Dynamic Dispatch
A complete guide to Ruby's method_missing — how it works, practical use cases, and how to implement it safely with respond_to_missing?.
Class Instance Variables in Ruby: Inheritance, Accessors, and Rails class_attribute
A deep dive into Ruby class instance variables — how they differ from class variables, how inheritance works, and how Rails class_attribute builds on them.
Class Variables in Ruby: @@var Explained
A complete guide to Ruby class variables (@@var) — how they work, how they behave with inheritance, thread safety concerns, and why class instance variables are usually preferred.
Ruby Class Extension Pattern: Adding Class Methods via Modules
Learn the Ruby class extension pattern — using self.included and extend(ClassMethods) to add both instance and class methods when a module is included.
Class Methods and Singleton Methods in Ruby
A complete guide to Ruby class methods — the three ways to define them, singleton methods, inheritance, and practical patterns.
Implementing a blank? Helper in Ruby
Learn how to implement and use a blank? helper in Ruby — handling nil, empty strings, whitespace, and falsy values cleanly.
Understanding class_eval, module_eval and instance_eval
Understanding class_eval, module_eval and instance_eval
Interface Inheritance vs Implementation Inheritance in Ruby and Go
Understand the difference between interface inheritance and implementation inheritance, with practical examples in Ruby and Go.
attr_checked函数在《ruby元编程》中的实现
attr_checked函数在《ruby元编程》中的实现
Dynamic Languages and Runtime Errors: Ruby's Late Binding Risks
Understand the risks of Ruby's dynamic nature — methods that fail only at runtime, how to mitigate them with tests and static analysis, and what this means for production code.
Debugging Capistrano Deploy Failures: Lessons in Dependency Management
A real-world debugging story: fixing a Capistrano deploy failure caused by a gem major version bump, with lessons on dependency management and semantic versioning.
Ruby: Strengths, Weaknesses, and When to Use It
An honest assessment of Ruby as a programming language — its strengths in expressiveness and developer happiness, its performance trade-offs, and where it fits in 2026.
在有多个模型关联操作的情况下，使用Callbacks保证数据的一致性
在有多个模型关联操作的情况下，使用Callbacks保证数据的一致性
ActiveRecord::Relation vs ActiveRecord Objects in Rails
Understand the difference between ActiveRecord::Relation and model objects in Rails — lazy loading, query chaining, and when to use find vs where.
Avoiding Duplicate HTML IDs in Rails Forms
How to avoid duplicate HTML element IDs in Rails when rendering multiple forms on the same page — using the namespace option and modern form helpers.
Equality and Comparison in Ruby: ==, eql?, equal?, <=>, and ===
A complete guide to Ruby's equality and comparison operators — ==, eql?, equal?, <=>, and === — what each means and when to use each.
Object-Oriented Programming in Ruby: Objects, Classes, and the Object Model
A deep dive into Ruby's object model — how objects, classes, modules, and the method lookup chain work, with comparisons to Python and Go.
How to Create a Gem For JavaScript and CSS Libraries
How to Create a Gem For JavaScript and CSS Libraries
Loops and Iteration in Ruby: A Complete Guide
A complete guide to loops and iteration in Ruby — times, upto, each, while, until, loop, map, select, and when to use each.
public, private, and protected Methods in Ruby
A complete guide to Ruby's method visibility: public, private, and protected — what they mean, how they work, and when to use each.
Understanding self in Ruby
A complete guide to understanding self in Ruby — what it refers to in different contexts, how it works in classes, modules, and singleton methods.
Instance Methods in Ruby: Definition, Binding, and Singleton Methods
A complete guide to Ruby instance methods — the three ways to define them, singleton methods, unbound methods, and dynamic method definition.
include vs extend in Ruby: Adding Methods to Classes and Objects
A complete guide to Ruby's include and extend — how they differ, when to use each, and the classic pattern for adding both instance and class methods via a module.
Sessions in Rails: How They Work and Best Practices
A complete guide to sessions in Rails — how they work, storage options, security considerations, and best practices for authentication.