[ 常見問題 ] Is there simpler (one-line) syntax to alias one class method?

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Question
I know I can do the following, and it's just 3 lines:

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1. class << self  
2.   alias :generate :new  
3. end  

But out of curiosity, is there a simpler way (without semicolons) like:

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1. class_alias :generate, :new  

Answers
Since Ruby 1.9 you can use the obj.singleton_class (Returns the singleton class of obj. ) method to access the singleton object of a class. This way you can also access thealias_method(new_name, old_name) method. The method itself is private so you need to invoke it with send. Here is your one liner:

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1. self.singleton_class.send(:alias_method, :generate, :new)  

For example:

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1. class MyObj  
2.     def objTest  
3.         puts "objTest"  
4.     end  
5.     def MyObj.clsTest  
6.         puts "clsTest"  
7.     end  
8.     self.singleton_class.send(:alias_method, :clsTest2, :clsTest)  
9. end  
10.   
11. obj = MyObj.new  
12. obj.objTest  
13. #obj.clsTest # NoMethodError: undefined method `clsTest' ...  
14. obj.class.clsTest  
15. MyObj.clsTest2  

Keep in mind though, that alias will not work here.

Supplement
* [ Ruby Gossip ] Basic : 類別 - 關於 self
* [ 文章收集 ] alias vs alias_method