# Is "ampersand-colon" a preferable way to pass a proc to a method in Rails source?

**URL:** <https://www.ruby-forum.com/t/is-ampersand-colon-a-preferable-way-to-pass-a-proc-to-a-method-in-rails-source/214747>\
**Category:** Deployment\
**Created:** [December 11, 2011, 3:29pm UTC](https://www.ruby-forum.com/t/is-ampersand-colon-a-preferable-way-to-pass-a-proc-to-a-method-in-rails-source/214747 "2011-12-11T15:29:20Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![luislavena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/0ea827/32.png) [@luislavena](https://www.ruby-forum.com/u/luislavena)\
**Post date:** [December 11, 2011, 3:29pm UTC](https://www.ruby-forum.com/t/is-ampersand-colon-a-preferable-way-to-pass-a-proc-to-a-method-in-rails-source/214747/1 "2011-12-11T15:29:20Z")

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Hello, i am trying to fix a bug in Rails, and also improve readability  
of the code i am coming across in this process. I have a question: is

map(&:to\_s)

preferred over

map { |n| n.to\_s }

?

I was going to use the first form, but decided to ask first.

Alexey.

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**Author:** ![4zy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/4/8491ac/32.png) [@4zy](https://www.ruby-forum.com/u/4zy)\
**Post date:** [December 11, 2011, 3:39pm UTC](https://www.ruby-forum.com/t/is-ampersand-colon-a-preferable-way-to-pass-a-proc-to-a-method-in-rails-source/214747/2 "2011-12-11T15:39:50Z")

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Sorry, this was probably a wrong forum to post this.