DZone Snippets is a public source code repository. Easily build up your personal collection of code snippets, categorize them with tags / keywords, and share them with the world

Snippets Manager

Snippets has posted 5883 posts at DZone. View Full User Profile

Using && Instead Of And

06.24.2010

| 1317 views |

        Source: <a href="http://www.themomorohoax.com/2008/12/08/and-vs-amperand-in-ruby">and vs && (double ampersand) in Ruby - Momoro Machine</a> [themomorohoax.com] via <a href="http://twitter.com/AkitaOnRails/status/16959633756">Twitter / Fabio Akita: RT @igrigorik: just learne ...</a> [twitter.com]
<snip>
Many people seem to prefer using and instead of && in Ruby, as it sounds more like speech.

However, do note that itâ€™s slightly different from using &&. The difference is important enough that I think you should avoid using and.

alien = true
speaks_english = false

# 1
alien and speaks_english ? 'hello' : '**silence**'
#=> "**silence**"

# 2
alien && speaks_english ? 'hello' : '**silence**'
#=> "**silence**"

# 3
speaks_english and alien ? 'hello' : '**silence**'
#=> false  # oops

# 4
speaks_english && alien ? 'hello' : '**silence**'
#=> "**silence**"

</snip>

Interestingly enough ...

alien = true
speaks_english = false

# 1
if alien and speaks_english then 'hello' else '**silence**' end
#=> "**silence**"

# 2
if alien && speaks_english then 'hello' else '**silence**' end
#=> "**silence**"

# 3
if speaks_english and alien then 'hello' else '**silence**' end
#=> "**silence**"

# 4
if speaks_english && alien then 'hello' else '**silence**' end
#=> "**silence**"

Tags: