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Day 4: #100DaysofCode - More Iterators

sincerelybrittany profile image Brittany ・2 min read

#100DaysofCode (75 Part Series)

1) Day 1 of #100DaysofCode - Understanding Iterators 2) Day 2: #100DaysofCode - I updated to Catalina and All HELL Broke Loose 3 ... 73 3) Day 3: #100DaysofCode - Oh No, SQL 4) Day 4: #100DaysofCode - More Iterators 5) Day 5 - #100DaysofCode - Setting up a Sinatra App 6) Day 6 : #100DaysofCode - Setting up a Sinatra App : Part 2 - Config.ru 7) Day 7: #100DaysofCode - Setting up a Sinatra App - Part 3 8) Day 8: #100DaysofCode - Setting up Sinatra Database - Part 4 9) Day 9: #100DaysofCode - ActiveRecord and a Database 10) Day 10: #100DaysofCode - ActiveRecord and a Database 11) Day 11 : #100DaysofCode - RESTful Routes 12) Day 12: #100DaysofCode and Day 1 of #Javascript30 13) Day 13 - #100DaysofCode - #Javascript30 - Day 2 - CSS + JS Clock 14) Day 14: #100DaysofCode - Finalized my Sinatra Project -Security 15) #Day 15: #100DaysofCode - View my Sinatra Project 16) Day 16 - #100DaysofCode - Understanding MVC 17) Day 17 : #100DaysofCode - Knowing your Ruby Version & what Errno::EADDRINUSE means is important! 18) Day 18 of #100daysofCode - 3 challenges 19) Day 19 of #100daysofCode - Hashes 101 20) Day 20: #100DaysofCode - Practice makes perfect 21) Day 21 : #100DaysofCode - Cascading Style Sheets 101 22) Day 22 - #100daysofCode - CSS 101 Part 2 23) Day 23 - #100DaysofCode - Updated My Portfolio 24) Day 24 - #100DaysofCode - Practicing CSS Grid and Emmet Shortcuts on VSCode 25) Day 25 - #100DaysofCode - Intro to Rails 26) Day 26 - #100DaysofCode - Accessing Rails Commands 27) Day 27 : #100DaysofCode - Still reviewing the basic rails concepts . . . 28) Day 28 : #100DaysofCode - Adding Dev.to blogs to personal page 29) Day 29 : #100DaysofCode - Very Simple Rails App CRUD Practice 30) Day 30 : #100DaysofCode - Very basic rails continued 31) Day 31 - #100DaysofCode - Rails Routes 101 32) Day 32 : #100DaysofCode - Resources for learning to code 33) Day 33 - #100DaysofCode - Setting up my app on Heroku 34) Day 34 - #100DaysofCode - New/edit action versus create/update action 35) Day 35 : #100DaysofCode - A Code Challenge Completed 36) Day 36 - #100DaysofCode - Rails form_for versus form_tag 37) Day 37 : #100DaysofCode - 30 seconds of code 38) Day 38 - #100DaysofCode - Built my first basic rails application 39) Day 39 : #100DaysofCode - I updated my github profile page 40) Day 40 : #100DaysofCode - I need project ideas 41) Day 41 : #100DaysofCode - Collaboration 42) Day 42 : #100DaysofCode - The Planning of a Project 43) Day 43 : #100DaysofCode - The Amazing Faker Gem 44) Day 44 : #100DaysofCode - Code or Youtube? 45) Day 45 : #100DaysofCode - Basic Nested Forms 46) Day 46 : #100DaysofCode - Still reviewing form_for 47) Day 47 : #100DaysofCode - How do you code? 48) Day 48 : #100DaysofCode - Code Along 49) Day 49 : #100DaysofCode - Still Coding Along 50) Day 50 : #100DaysofCode - Keep Coding Along 51) Day 51 : #100DaysofCode - Code Along 52) Day 52 : #100DaysofCode - No Wifi, No Problem 53) Day 53: #100DaysofCode - Created user log in and log out functionality 54) Day 54 : #100DaysofCode -Review on setting up log in & sign up 55) Day 55 : #100DaysofCode - In Need of Advice on Reading Poorly Written Documentation 56) Day 56 : #100DaysofCode - A Tweet - Devise - Users 57) Day 57 : 100DaysofCode - Remembering to Git Commit Often 58) Day 58 : #100DaysofCode - Beginning to Learn Python 59) Day 59 : #100DaysofCode - Focused on My Rails Project 60) Day 60 : #100DaysofCode - CSS in Rails 61) Day 61 : #100DaysofCode - Omniauth? 62) Day 62 : #100DaysofCode - Sign in using a Third Party, Rails 63) Day 63 : #100DaysofCode - Refactoring 64) Day 64 : #100DaysofCode - Still Playing Around With OmniAuth 65) Day 65 : #100DaysofCode - Second Rails Project - I Want to Try Self-Referencing Tables 66) Day 66 : #100DaysofCode - Creating a Follow/Unfollow in Rails 67) Day 67 - #100DaysofCode - Adding Categories to Rails App 68) Day 68 - #100DaysofCode - Making Sure Only Admin Can CRUD Application - W/O CanCanCan 69) Day 69 : #100DaysofCode - Coming Up With An App Idea 70) Day 70 : #100DaysofCode - Taking A Break And Learning From Others Is Important 71) Day 71 : #100DaysofCode - Re-route rails app after log in with devise 72) Day 72 : #100DaysofCode - Still Trying To Get API To Work 73) Day 73 : #100DaysofCode - Prepared for Assessment 74) Day 74 : #100DaysofCode - Finished Adding Categories 75) Day 75 : #100DaysofCode - My Rails Project

I wanted to review some more iterators as promised in my previous post

Times Iterator

The Times Iterator helps when you want to receive something n number of times. For example, if you wanted to say "HA!" six times you would use the times iterator like so:

6.times do
  puts "HA!"
end

This will print "Ha!" to the screen 6 times. Like so:

HA!
HA!
HA!
HA!
HA!
HA!

You could also take an argument and use interpolation like so:

5.times do |name|
  puts "Hello! #{name}"
end

Just like an array index, the times index starts at 0. So the output above would look like the following:

Hello! 0
Hello! 1
Hello! 2
Hello! 3
Hello! 4

Upto Iterator

The Upto Iterator allows you to could up to a number of your choice. But it has to be an ascending number, otherwise you will not receive output. I feel like this iterator is perfect for when you are trying to output a specific range of numbers, like so:

10.upto(20) do |n|    
  puts n    
end  

Output:

10
11
12
13
14
15
16
17
18
19
20

Downto Iterator

The Downto Iterator is pretty much the opposite of the Upto Iterator. In that it gives you a range of numbers descending. But just like the upto iterator, it has to be in a descending order, otherwise you will not receive output. Like so:

10.downto(5) do |n|    
  puts n    
end  

Output:

10
9
8
7
6
5

Step Iterator

The Step Iterator allows you to skip values by a number. So if you wanted to count by 5 to 30, you would use the step iterator like this:

(0..30).step(5) do|i| 
    puts i 
end

Output:

0
5
10
15
20
25
30

Each_Line Iterator

The Each_line Iterator is used to iterate over a new line in a string.

Syntax

string.each_line do |variable_name|
# code to be executed
end

Example

"Now\nwe\nunderstand\niterators.".each_line do|i| 
puts i 
end

Output:

Now
we
understand
iterators.

Sources used for this blog:

#100DaysofCode (75 Part Series)

1) Day 1 of #100DaysofCode - Understanding Iterators 2) Day 2: #100DaysofCode - I updated to Catalina and All HELL Broke Loose 3 ... 73 3) Day 3: #100DaysofCode - Oh No, SQL 4) Day 4: #100DaysofCode - More Iterators 5) Day 5 - #100DaysofCode - Setting up a Sinatra App 6) Day 6 : #100DaysofCode - Setting up a Sinatra App : Part 2 - Config.ru 7) Day 7: #100DaysofCode - Setting up a Sinatra App - Part 3 8) Day 8: #100DaysofCode - Setting up Sinatra Database - Part 4 9) Day 9: #100DaysofCode - ActiveRecord and a Database 10) Day 10: #100DaysofCode - ActiveRecord and a Database 11) Day 11 : #100DaysofCode - RESTful Routes 12) Day 12: #100DaysofCode and Day 1 of #Javascript30 13) Day 13 - #100DaysofCode - #Javascript30 - Day 2 - CSS + JS Clock 14) Day 14: #100DaysofCode - Finalized my Sinatra Project -Security 15) #Day 15: #100DaysofCode - View my Sinatra Project 16) Day 16 - #100DaysofCode - Understanding MVC 17) Day 17 : #100DaysofCode - Knowing your Ruby Version & what Errno::EADDRINUSE means is important! 18) Day 18 of #100daysofCode - 3 challenges 19) Day 19 of #100daysofCode - Hashes 101 20) Day 20: #100DaysofCode - Practice makes perfect 21) Day 21 : #100DaysofCode - Cascading Style Sheets 101 22) Day 22 - #100daysofCode - CSS 101 Part 2 23) Day 23 - #100DaysofCode - Updated My Portfolio 24) Day 24 - #100DaysofCode - Practicing CSS Grid and Emmet Shortcuts on VSCode 25) Day 25 - #100DaysofCode - Intro to Rails 26) Day 26 - #100DaysofCode - Accessing Rails Commands 27) Day 27 : #100DaysofCode - Still reviewing the basic rails concepts . . . 28) Day 28 : #100DaysofCode - Adding Dev.to blogs to personal page 29) Day 29 : #100DaysofCode - Very Simple Rails App CRUD Practice 30) Day 30 : #100DaysofCode - Very basic rails continued 31) Day 31 - #100DaysofCode - Rails Routes 101 32) Day 32 : #100DaysofCode - Resources for learning to code 33) Day 33 - #100DaysofCode - Setting up my app on Heroku 34) Day 34 - #100DaysofCode - New/edit action versus create/update action 35) Day 35 : #100DaysofCode - A Code Challenge Completed 36) Day 36 - #100DaysofCode - Rails form_for versus form_tag 37) Day 37 : #100DaysofCode - 30 seconds of code 38) Day 38 - #100DaysofCode - Built my first basic rails application 39) Day 39 : #100DaysofCode - I updated my github profile page 40) Day 40 : #100DaysofCode - I need project ideas 41) Day 41 : #100DaysofCode - Collaboration 42) Day 42 : #100DaysofCode - The Planning of a Project 43) Day 43 : #100DaysofCode - The Amazing Faker Gem 44) Day 44 : #100DaysofCode - Code or Youtube? 45) Day 45 : #100DaysofCode - Basic Nested Forms 46) Day 46 : #100DaysofCode - Still reviewing form_for 47) Day 47 : #100DaysofCode - How do you code? 48) Day 48 : #100DaysofCode - Code Along 49) Day 49 : #100DaysofCode - Still Coding Along 50) Day 50 : #100DaysofCode - Keep Coding Along 51) Day 51 : #100DaysofCode - Code Along 52) Day 52 : #100DaysofCode - No Wifi, No Problem 53) Day 53: #100DaysofCode - Created user log in and log out functionality 54) Day 54 : #100DaysofCode -Review on setting up log in & sign up 55) Day 55 : #100DaysofCode - In Need of Advice on Reading Poorly Written Documentation 56) Day 56 : #100DaysofCode - A Tweet - Devise - Users 57) Day 57 : 100DaysofCode - Remembering to Git Commit Often 58) Day 58 : #100DaysofCode - Beginning to Learn Python 59) Day 59 : #100DaysofCode - Focused on My Rails Project 60) Day 60 : #100DaysofCode - CSS in Rails 61) Day 61 : #100DaysofCode - Omniauth? 62) Day 62 : #100DaysofCode - Sign in using a Third Party, Rails 63) Day 63 : #100DaysofCode - Refactoring 64) Day 64 : #100DaysofCode - Still Playing Around With OmniAuth 65) Day 65 : #100DaysofCode - Second Rails Project - I Want to Try Self-Referencing Tables 66) Day 66 : #100DaysofCode - Creating a Follow/Unfollow in Rails 67) Day 67 - #100DaysofCode - Adding Categories to Rails App 68) Day 68 - #100DaysofCode - Making Sure Only Admin Can CRUD Application - W/O CanCanCan 69) Day 69 : #100DaysofCode - Coming Up With An App Idea 70) Day 70 : #100DaysofCode - Taking A Break And Learning From Others Is Important 71) Day 71 : #100DaysofCode - Re-route rails app after log in with devise 72) Day 72 : #100DaysofCode - Still Trying To Get API To Work 73) Day 73 : #100DaysofCode - Prepared for Assessment 74) Day 74 : #100DaysofCode - Finished Adding Categories 75) Day 75 : #100DaysofCode - My Rails Project

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Brittany

@sincerelybrittany

Web Developer | Software Engineer 👩🏾‍💻 | Determined | Music & Dance | #100DaysofCode | #WomenWhoCode

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