User input stored as a string ($stdin.gets.chomp)

Following along with LRtHW on exercise 31 and I was wondering why the author was testing the user input as a string.

There was an exercise that covered gets.chomp but I never thought about it returning a string.  Then I found this documentation...

http://www.ruby-doc.org/docs/Tutorial/part_02/user_input.html

I was assuming that it would take the user input as is but the above link states...

1. chomp is a string method (String#chomp).
2. gets returns (gives you back) a string.

When I changed the code in the exercise from...

puts "You enter a dark room with two doors. Do you go through door #1 or door #2?"

print "> "

door = $stdin.gets.chomp

if door == "1"

  puts "There's a giant bear here eating cheese cake. What do you do?"

end

...to...

puts "You enter a dark room with two doors. Do you go through door #1 or door #2?"

print "> "

door = $stdin.gets.chomp.to_i

if door == 1

  puts "There's a giant bear here eating cheese cake. What do you do?"

end

..it worked as expected.

Ruby naming

Following along with the online LRTHW exercises and lesson 25. I copied the code as it was stated from the web page. Well, I typed it in manually rather than doing a copy and paste. Just to take a shortcut to type it in as fast as possible, I didn't capitalize the module name and I got the following error...

2.1.3 :001 > require "./ex25.rb"

SyntaxError: /home/.../ruby/ex25.rb:1: class/module name must be CONSTANT

from /home/.../.rvm/rubies/ruby-2.1.3/lib/ruby/site_ruby/2.1.0/rubygems/core_ext/kernel_require.rb:54:in `require'

from /home/.../.rvm/rubies/ruby-2.1.3/lib/ruby/site_ruby/2.1.0/rubygems/core_ext/kernel_require.rb:54:in `require'

from (irb):1

from /home/.../.rvm/rubies/ruby-2.1.3/bin/irb:11:in `<main>'

After going back and capitalizing the module name, function names and references to the functions, I was able to get it run without error.

2.1.3 :001 > require "./ex25.rb"

 => true 

Found official documentation that discusses naming.  The exercise didn't cover the topic of naming...

http://www.ruby-doc.org/docs/ruby-doc-bundle/UsersGuide/rg/constants.html

Escape sequence r

While trying out the escape sequence 'r', I again didn't get the results I expected.

I thought that there would be a blank line after the word return when keying this in...

2.1.3 :001 > puts "return\r"
return
 => nil

After finding out about \b, I decided to put a space after \r and the double quotation mark and this was what I got...

2.1.3 :002 > puts "return\r "
 eturn
 => nil

This confused me even more until a few minutes later when I remembered that a carriage return was not what I thought it was.  I remembered reading some documentation some time ago that \r returned the "focus", if you will, to the beginning of the line and that the line feed was a separate escape sequence altogether.  That wasn't the terminology I read but that's how I remembered it.

2.1.3 :003 > puts "return\f"
return

 => nil

This is what I was expecting at first when using \r.  I do know that the \f switch/option just moves the "focus" down a line in the same spot...kind of like using a typewriter and moving the page up one line.  The type writer is going to type right where it's at unless it's moved to the beginning of that line.  Necessary to know if using Ruby to look through strings or text files etc.

Starting at the beginning of the next line (just like you would with a typewriter), I'd need to use \r\f options like so...

2.1.3 :004 > puts "return\r\f"
return

 => nil

Escape sequence b

I'm currently reading the website (online e-book) Learn Ruby the Hard Way and I'm on exercise 10.

It covers using the escape sequence with the various options.

I was stuck for a moment on why it wasn't working like I thought it should.

2.1.3 :001 > puts "backspace\b"
backspace
 => nil

I felt the entry should have removed the 'e' but the 'e' still showed up.  On another attempt, I got the result I was looking for.

2.1.3 :002 > puts "backspace\b "
backspac
 => nil

Putting a space between the letter 'b' and the double quote worked.  I have no technical explanation for this. My guess is that the backslash b is not given any space to "do it's thing".  I've googled but couldn't find anything on this topic.  Any comments welcome.  If I do find the explanation, I'll post what I find.