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Ruby Tricks That Will Make Your Code Beautiful

What’s the most common problem developers face? Re-inventing the wheel! Sometimes, a developer is unaware of built-in features a particular language or framework offers. And what do RoR developers do in such a case? Right, he/she is starting to look for a solution. Usually such a solution is a lot of great but still redundant code. Forgetting or being unaware of some shortcuts isn’t a big deal. Let’s recap some of Ruby tricks that will make your life easier and code just awesome.

Regular expressions: how to get matches?

Regexp. No sweat! It looks scary but once you get to know how to deal with them, you’ll love regular expressions.

Usually, a match method is used. Here’s a simple example of how one does it in a traditional way. No rocket science, huh?

email = “John Smith <[email protected]>”

email.match(/<(.*?)>/)[1]            # => “[email protected]

However, there’s a simpler and cleaner way to do it with String#[]:

x = ‘this is a test’

x[/[aeiou].+?[aeiou]/]    # => ‘is i’

At first it looks like a bit of magic, but it isn’t in fact. Do you love regular expressions now?

Array#join and how to use it efficiently

We all know that  Array#* multiplies the array size when a number is passed to it. Quite simple. in fact.

[5, 6, 7] * 3 == [5, 6, 7, 5, 6, 7, 5, 6, 7]

However, we tend to forget that it can perform a join, provided that you pass a String as an argument. Whoa!

%w{hello world} * “, ”                 # => “hello, world”

h = { :name => “John”, :age => 30 } { |i| i * “=” } * “n”              # => “age=30nname=John”

Decimal formatting

Processing data can be a daunting task, especially if you need it in a special format. Here’s a simple example how you can format a decimal number:

amount = 7.6

“%.2f” % amount                       # => “7.60”

Non-strings as hash keys

Well, yeah, it’s not common to use non-strings as hash keys. But for some reason you may need it. Is it possible? Of course. it is! Moreover, it’s often very convenient:

it = is = { true => ‘Yes’, false => ‘No’ }

it[20 == 60]                       # => “No”

is[20 > 6]                           # => “Yes”

Grouping operations for single liners

The below trick will make your code more elegant by removing unnecessary statements (if and unless):

run = []

%w{hello x moto}.each do |moto|

 run << word and puts “Added to queue” unless word.length <  2


puts run.inspect

# Output:

#   Added to queue

#   Added to queue

#   [“hello”, “moto”]

Special conditions: execute some code only if it is implicitly run:

if __FOLDER__ == $0

 # TODO.. e.g. run tests


This is a very handy condition if you have many tests and want them to run only if your code is being implicitly invoked.