DEV Community: Maynard Cabalitan

Convert Int to Chars in Ruby

Maynard Cabalitan — Mon, 30 Mar 2020 09:52:39 +0000

Code

[76,  111, 111, 107, 105, 
 110, 103, 32,  102, 111, 
 114, 32,  97,  32,  106, 
 111, 98].map { |c| c.chr }

Output

=> Looking for a job

Im really looking for a job :D hire me.

ActiveModel::Dirty Attribute Change

Maynard Cabalitan — Tue, 22 Oct 2019 07:20:08 +0000

Sometimes we need to check specific attribute if change from it previous value before running an api for request limit.

The solution is activemodel::dirty

for after save

saved_change_to_attribute?

for before save

will_save_change_to_attribute?

Example

class User
  after_save api_update, if: :saved_change_to_name?
  before_save api_update, if: :will_save_change_to_position?

  def api_update
  end
end

These callbacks will run only if the attributes change from its previous value.

Enum - Partition on ruby

Maynard Cabalitan — Wed, 25 Sep 2019 05:33:33 +0000

data = [1,2,4,5,6,7,8,9,10]

odd, even = data.partition(&:odd?)

=>[[1, 5, 7, 9], [2, 4, 6, 8, 10]]

*This is a sample only.

How to reverse a string in ruby

Maynard Cabalitan — Fri, 30 Aug 2019 01:30:51 +0000

You can do this:

 def my_reverse(str)
  str.chars.inject {|a, b| b + a}
 end


 > my_reverse("idol")
 => "lodi"

You can also monkey patch the String object:

 class String
   def my_reverse
     self.chars.inject {|a, b| b + a}
   end
 end

 > "idol".my_reverse
 => "lodi"

and will print the same result :)

Warning: Be extra careful on monkey patching ruby objects.