Ask A Question


You’re not receiving notifications from this thread.

Solving FizzBuzz in Ruby Discussion

Discussion for Solving FizzBuzz in Ruby

Love this episode Chris.

Would love to see more.


I tried the second solution and got an error "no implicit conversion of Fixnum into String" when using rails c with Pry; and NoMethodError: undefined method 'blank?' for String:Class when using irb:

tom@thomas:~/paul$ irb
2.3.1 :001 > 1.upto(100) do |i|
2.3.1 :002 > str = ""
2.3.1 :003?>
2.3.1 :004 > str += "Fizz" if i % 3 == 0
2.3.1 :005?> str += "Buzz" if i % 5 == 0
2.3.1 :006?> str += i if str.blank?
2.3.1 :007?>
2.3.1 :008 > puts str
2.3.1 :009?> end
NoMethodError: undefined method `blank?' for "":String
from (irb):6:in `block in irb_binding'
from (irb):1:in `upto'
from (irb):1

What am I doing wrong?


Oh you know what, I probably had access to ActiveSupport while I was doing that.

Add this line at the beginning if you have the active_support gem installed.

require 'active_support/core_ext'

The blank? method doesn't come from Ruby but most of my work being in Rails I'm so used to having it around. :)


You can use native Ruby string method .empty?


if you use pry works.




Great episode Chris, would love to see more like this!

If anyone else is interested, a cool site to work on problems similar to FizzBuzz is I try to do one a week (Although it's been quite some time since my last one).

Reply is also noteworthy.


Okay I'm hitting an error and I understand what it's saying but I'm more confused as to why it's happening.

`def fizzbuzz(start_num, end_num)
start_num.upto(end_num) do |n|
str = ""
str += "fizz" if n % 3 == 0
str += "buzz" if n % 5 == 0
str += n if str.empty?
puts str

fizzbuzz(1, 100)`

And when I run it....
`assessment_109.rb:7:in `+': no implicit conversion of Fixnum into String (TypeError)`

Changing the += to a = in the last line works (and since it's an empty string, it outputs the same)

Did anyone else run into this?
Is this just a typo that I'm over thinking or am I completely missing something here?

Thanks! :)


You can do str += n.to_s if str.empty? instead because it's an integer and needs to be converted to a string before you can add those together.

Andrew Cockerham Andrew Cockerham

Super helpful - would love more of this!


love it

Trevor Johnson Trevor Johnson

I hope you do more of these Chris. It's always great to see different ways people solve coding challenges.

yoshitakame yoshitakame

I tried to solve the problem without defining empty string. But the result might be a bit more complicated.

1.upto(100) do |i|
str = 'fizz' if (i % 3).zero?
str = str ? 'fizzbuzz' : 'buzz' if (i % 5).zero?
str = i unless str
puts str

It's helpful to learn how to write clean and clear code!


Hi Chris, really like this example. I have a couple of pieces of feedback since I tried to run it and encountered issues. Line 19 needs to be str = i instead of str += i. Since str is started as a string, I get "no implicit conversion of Integer into String" when I try to add the i. Also, str.blank? works if you are in an ActiveSupport context. Otherwise, str.empty? is available.


I realise this is an old video but for anyone having an issue with line #19 "if str.blank?"

I used str.nil? and it works

Join the discussion
Create an account Log in

Want to stay up-to-date with Ruby on Rails?

Join 84,111+ developers who get early access to new tutorials, screencasts, articles, and more.

    We care about the protection of your data. Read our Privacy Policy.