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Feature #17663

Updated by RichOrElse (Ritchie Buitre) 8 months ago

**Enumerator#with** yields each element along with the arguments 
 ``` ruby 
 class Enumerator 
   def with(*options) 
     return to_enum(:with, *options) unless defined? yield 

     each do |entry| 
       yield entry, *options 
     end 
   end 
 end 
 ``` 

 I found **Enumerator#with_object** method awkward to use. Suppose we have a proc that accepts more than 1 argument. 
 ``` ruby 
 format = proc do |value, *option| 
   value.to_s(*option) 
 end 
 ```  
 Normally to apply the argument we enclosed it in a block, like so: 
 ``` ruby 
 (10..15).map { |n| format.(n, 16) } # => ["a", "b", "c", "d", "e", "f"] 
 ``` 
 I found Here's the equivalent code using **Enumerator#with_object** method awkward to use. method. 
 ``` ruby 
 (10..15).each.with_object(16).map(&format) # => ["a", "b", "c", "d", "e", "f"] 
 ``` 
 Tried simplifying this code further, but **Enumerator#with_object** ignores the given block and just returns the argument. 
 ``` ruby 
 (10..15).map.with_object(16, &format) # => 16 
 ``` 
 Compare to how concise this line using **Enumerator#with**  
 ``` ruby 
 (10..15).map.with(16, &format)    # => ["a", "b", "c", "d", "e", "f"] 

 ``` 


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