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From: foonlyboy@gmail.com
To: ruby-core@ruby-lang.org
Subject: [ruby-core:92560] [Ruby trunk Feature#15829] Object#then_if(condition){}
Date: Sun, 05 May 2019 18:35:44 +0000 (UTC)	[thread overview]
Message-ID: <redmine.journal-77923.20190505183544.cbc312e0a5d5da86@ruby-lang.org> (raw)
In-Reply-To: redmine.issue-15829.20190505182618@ruby-lang.org

Issue #15829 has been updated by foonlyboy (Eike Dierks).


``` ruby
class Object
  def then_if(condition, &block)
    if condition
      self.then(&block)
    else
      self
    end
  end
end

```


----------------------------------------
Feature #15829: Object#then_if(condition){}
https://bugs.ruby-lang.org/issues/15829#change-77923

* Author: foonlyboy (Eike Dierks)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
----------------------------------------
I'd like to propose some sugar to Object#then

There should be Object#then_if(condition, &block)
 
The block should only be applied when the condition is true,
otherwise the object should be returned without applying the block.

Rationale:

I frequently use Object#then with Rails to extend queries like this:

```
foo.then {|query|
  if(condition)
   query.where(zip:zap)
  else
   query
  end
}
```

by using the proposed Object#then_if the example could be simplified to:

```
foo.then_if(condition) {|query|
   query.where(zip:zap)
}
```

I believe that this also applies to a lot of other use cases,
i.e. only applying some transformation if some condition is true,
but otherwise leaving the result untouched.















-- 
https://bugs.ruby-lang.org/

  parent reply	other threads:[~2019-05-05 18:35 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <redmine.issue-15829.20190505182618@ruby-lang.org>
2019-05-05 18:26 ` [ruby-core:92559] [Ruby trunk Feature#15829] Object#then_if(condition){} foonlyboy
2019-05-05 18:35 ` foonlyboy [this message]
2019-05-05 18:48 ` [ruby-core:92561] " foonlyboy
2019-05-05 20:30 ` [ruby-core:92564] " foonlyboy
2019-05-05 20:51 ` [ruby-core:92565] " sawadatsuyoshi
2019-05-11  7:13 ` [ruby-core:92620] " nobu
2019-05-11 12:11 ` [ruby-core:92621] " sawadatsuyoshi
2019-07-29  6:58 ` [ruby-core:93967] [Ruby master " ko1
2019-12-15  8:22 ` [ruby-core:96245] " masafumi.o1988

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