# Enumerators concatenation possible?

**URL:** <https://www.ruby-forum.com/t/enumerators-concatenation-possible/208483>\
**Category:** Ruby\
**Created:** [June 20, 2011, 3:03am UTC](https://www.ruby-forum.com/t/enumerators-concatenation-possible/208483 "2011-06-20T03:03:14Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![dubstep](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/cdc98d/32.png) [@dubstep](https://www.ruby-forum.com/u/dubstep)\
**Post date:** [June 20, 2011, 3:03am UTC](https://www.ruby-forum.com/t/enumerators-concatenation-possible/208483/1 "2011-06-20T03:03:14Z")

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Hi,

just curious if it’s possible to concatenate two instances of Enumerator  
class. For example

irb(main):001:0\> e1 = 0.upto(3)  
=\> #\<Enumerator: 0:upto(3)\>  
irb(main):002:0\> e2 = 4.step(10\*\*6,3)  
=\> #\<Enumerator: 4:step(1000000, 3)\>  
irb(main):003:0\> (e1 + e2).each {|i| … do some stuff … }

# throws NoMethodError because ‘+’ is not defined for Enumerators

I’m looking for some way/trick how to join e1 with e2 without expanding  
them to Arrays or writing own ‘concat’ method implementation.

Thanks.

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<div class="post-metadata">

**Author:** ![davidu](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/cc9497/32.png) [@davidu](https://www.ruby-forum.com/u/davidu)\
**Post date:** [June 20, 2011, 10:07pm UTC](https://www.ruby-forum.com/t/enumerators-concatenation-possible/208483/2 "2011-06-20T22:07:24Z")

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David U. wrote in post #1006253:

> just curious if it’s possible to concatenate two instances of Enumerator  
> class.

No, but it has been suggested (and rejected) here:

> **[Feature #709: Enumerator#+ - Ruby master - Ruby Issue Tracking System](https://redmine.ruby-lang.org/issues/709)**
>
> Redmine

which also gives you an implementation you can use.