---
title: "Ruby 2.5 added yield_self"
description: "Method to yield the receiver to the given block."
canonical_url: "https://www.bigbinary.com/blog/ruby-2-5-added-yield_self"
markdown_url: "https://www.bigbinary.com/blog/ruby-2-5-added-yield_self.md"
---

# Ruby 2.5 added yield_self

Method to yield the receiver to the given block.

- Author: Vijay Kumar Agrawal
- Published: December 12, 2017
- Categories: Ruby 2.5, Ruby

Ruby 2.5 added a new method named
[yield_self](https://bugs.ruby-lang.org/issues/6721). It yields the receiver to
the given block and returns output of the last statement in the block.

```ruby
irb> "Hello".yield_self { |str| str + " World" }
  => "Hello World"
```

#### How is it different from `try` in Rails ?

Without a method argument [try](https://apidock.com/rails/v4.2.7/Object/try)
behaves similar to `yield_self`. It would yield to the given block unless the
receiver is nil and returns the output of the last statement in the block.

```ruby
irb> "Hello".try { |str| str + " World" }
  => "Hello World"
```

Couple of differences to note are, `try` is not part of `Ruby` but `Rails`. Also
`try`'s main purpose is protection against `nil` hence it doesn't execute the
block if receiver is `nil`.

```ruby
irb> nil.yield_self { |obj| "Hello World" }
  => "Hello World"

irb> nil.try { |obj| "Hello World" }
  => nil
```

#### What about `tap`?

`tap` also is similar to `yield_self`. It's part of Ruby itself. The only
difference is the value that is returned. `tap` returns the receiver itself
while `yield_self` returns the output of the block.

```ruby
irb> "Hello".yield_self { |str| str + " World" }
  => "Hello World"

irb> "Hello".tap { |str| str + " World" }
  => "Hello"
```

Overall, `yield_self` improves readability of the code by promoting chaining
over nested function calls. Here is an example of both the styles.

```ruby
irb> add_greeting = -> (str) { "HELLO " + str }
irb> to_upper = -> (str) { str.upcase }

# with new `yield_self`
irb> "world".yield_self(&to_upper)
            .yield_self(&add_greeting)
  => "HELLO WORLD"

# nested function calls
irb> add_greeting.call(to_upper.call("world"))
  => "HELLO WORLD"

```

`yield_self` is part of `Kernel` and hence it's available to all the objects.

## Links

- [Human page](https://www.bigbinary.com/blog/ruby-2-5-added-yield_self)