New to ruby, "requier" not working?


#1

Hello,

I'm trying to learn ruby from the Poignant guide to Ruby

(http://poignantguide.net/ruby/chapter-4.html) and have run into a
problem. In chapter 4 the simple word replacement example is the
first use of the require statement. It does not work for me. I’m on
OS 10.3, ruby 1.8.2 and my directory structure is :

~/projects/test.rb
~/projects/wordlist.rb

test.rb starts with:
require ‘wordlist’

and wordlist.rb just has:
words = {
‘starmonkeys’ => ‘Phil and Pete, those prickly chancellors of the
New Reich’,
‘catapult’ => ‘chucky go-go’, ‘firebomb’ => ‘Heat-Assisted Living’,
‘Nigeria’ => “Ny and Jerry’s Dry Cleaning (with Donuts)”,
‘Put the kabosh on’ => ‘Put the cable box on’
}

When i try and run test.rb it says that words is an undefined variable.
If i put the definition of words directly into the test.rb file it
works just fine.

I’m really frustrated with this so i could really use some advice.
I’ve tried all the permutations of require “wordlist”, require
“wordlist.rb” require ‘wordlist.rb’ require “./wordlist.rb” and
nothing works. I can’t get much farther until i figure out how to get
require working.

Thanks,
Dave.


#2

~/projects/test.rb
~/projects/wordlist.rb

test.rb starts with:
require ‘wordlist’

and wordlist.rb just has:
words = {
‘starmonkeys’ => ‘Phil and Pete, those prickly chancellors of the
New Reich’,
‘catapult’ => ‘chucky go-go’, ‘firebomb’ => ‘Heat-Assisted Living’,
‘Nigeria’ => “Ny and Jerry’s Dry Cleaning (with Donuts)”,
‘Put the kabosh on’ => ‘Put the cable box on’
}

When i try and run test.rb it says that words is an undefined variable.
If i put the definition of words directly into the test.rb file it
works just fine.

Dave, I am a newbie also. From the manual “require” and “load” are
similar. Maybe try “load ‘wordlist.rb’”. Possibly your default
directory is not ~/projects/ so the file cannot be found.

…Arch


#3

Hi

Take a look at this thread:
http://groups.google.com/group/comp.lang.ruby/browse_thread/thread/a1324b2ea0f23839

or via ruby-talk:
http://blade.nagaokaut.ac.jp/cgi-bin/vframe.rb/ruby/ruby-talk/100895?100721-101680

Clayton


#4

See also:

http://groups.google.com/group/comp.lang.ruby/browse_frm/thread/1adec0436f5d2b07


#5

On 12/29/05, Justin C. removed_email_address@domain.invalid wrote:

~/projects/wordlist.rb
‘Nigeria’ => “Ny and Jerry’s Dry Cleaning (with Donuts)”,
When you require a file, the local variables in that file stay in that
scope, and are not imported into the current scope. To be able to access
them, you must make them global.

actually, you could use an instance variable too @words = { … }
works just fine. If you don’t intend to change it, use a constant.

Otherwise, you can use an instance variable which is generally better
than a global.

sandal@karookachoo:~/Shared$ cat foo.rb
@something = “hello”
sandal@karookachoo:~/Shared$ ruby -e “require ‘foo’; puts @something
hello

Hope this helps
-Greg

PS: Has anyone noticed that my code examples seem to come from a
different shell EVERY time? I need to learn to stick to a machine for
more than a week :slight_smile:


#6

David Just wrote:

Hello,

I’m trying to learn ruby from the Poignant guide to Ruby
(http://poignantguide.net/ruby/chapter-4.html) and have run into a
problem. In chapter 4 the simple word replacement example is the
first use of the require statement. It does not work for me. I’m on
OS 10.3, ruby 1.8.2 and my directory structure is :

~/projects/test.rb
~/projects/wordlist.rb

test.rb starts with:
require ‘wordlist’

and wordlist.rb just has:
words = {
‘starmonkeys’ => ‘Phil and Pete, those prickly chancellors of the
New Reich’,
‘catapult’ => ‘chucky go-go’, ‘firebomb’ => ‘Heat-Assisted Living’,
‘Nigeria’ => “Ny and Jerry’s Dry Cleaning (with Donuts)”,
‘Put the kabosh on’ => ‘Put the cable box on’
}

This has come up on the list before…
‘words’ needs to be a global variable or constant. It’s basically a typo
in the tutorial.
Changing it to Words will get you a constant, changing it to $words will
get you a global variable.

When you require a file, the local variables in that file stay in that
scope, and are not imported into the current scope. To be able to access
them, you must make them global.

-Justin