Ruby » Ruby master

Feature #16460

Updated by sawa (Tsuyoshi Sawada) over 4 years ago

Hello! This is my first time filing an issue and I was unable to find anything similar. I apologize if one already exists. 

 In other languages (such as JavaScript, Swift, and Crystal), it is possible to have two names for a given keyword argument: one that is used in method invocation, and one used in the method definition. Here is an example from Crystal (which has syntax very similar to Ruby): 

 ```crystal 
 def increment(value, by amount) 
   value + amount 
 end 

 increment(value: 5, by: 10) 
 ``` 

 This helps create more readable method invocations and definitions. It would be especially helpful in Ruby as the language lacks a destructuring syntax for hashes/keyword args. This is unlike JavaScript, where you can do something like: 

 like  
 ```javascript 
 const { nameOfOneProperty: newNameForTheProperty, nameOfAnotherProperty: newNameForTheOtherProperty } = foo; 
 ``` 

 where `foo` is a JavaScript Object that has the properties `nameOfOneProperty` or `nameOfAnotherProperty` (If it did not have either of them, the corresponding identifiers (newNameForTheProperty and newNameForTheOtherProperty would be initialized to undefined). 

 


 I'm thinking that such a change would pair nicely with the new 3.0 keyword argument changes. A suggested syntax might be 

 ```ruby 
 def name(external_name internal_name:) 
   # ... 
 end 

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