Hi I am new to ruby and have recently started learning the same.I have written below ruby program which runs perfectly.
But this all program is written in a single file.I want to place each class in a different file and use one more file to execute all.ie like we do in java.[One main method to start the program] How can i run this program like this.
When i tried keeping each class in individual file and tried executing the same it started giving errors like method not found.
class Vehical
attr_accessor :odometer
attr_accessor :gas_used
def accelrate
puts " Floor It"
end
def sound_horn
puts "Beep! Beep!"
end
def steer
puts "Turn front 2 wheels"
end
def mileage
#odometer /#gas_used
end
end
class Truck < Vehical
end
class Motercycle < Vehical
end
class Car < Vehical
end
truck = Truck.new
truck.steer
car = Car.new
car.odometer = 11432
car.gas_used = 366
puts "Lifetime MPG:"
puts car.mileage
Below are few options:
Use require_relative to load those files into main file.
require_relative "vehical"
require_relative "truck"
require_relative "motor_cycle"
require_relative "car"
Use $:.unshift File.dirname(__FILE__) in main file to add its location to Ruby Load path, and use require "dependent-file-name-without-extension" in main file.
$:.unshift File.dirname(__FILE__)
require "vehical"
require "truck"
require "motor_cycle"
require "car"
Use -I <folder> when running the program. Example: ruby -I . main.rb
-Idirectory specify $LOAD_PATH directory (may be used more than once)
Related
I have a module and class in a file lib/crawler/page-crawler.rb that looks like this:
require 'oga'
require 'net/http'
require 'pry'
module YPCrawler
class PageCrawler
attr_accessor :url
def initialize(url)
#url = url
end
def get_page_listings
body = Net::HTTP.get(URI.parse(#url))
document = Oga.parse_html(body)
document.css('div.result')
end
newpage = PageCrawler.new "http://www.someurl"
#listings = newpage.get_page_listings
#listings.each do |listing|
bizname = YPCrawler::ListingCrawler.new listing['id']
end
end
end
Then I have another module & class in another file lib/crawler/listing-crawler.rb that looks like this:
require 'oga'
require 'pry'
module YPCrawler
class ListingCrawler
def initialize(id)
#id = id
end
def extract_busines_name
binding.pry
end
end
end
However, when I try to run this script ruby lib/yp-crawler.rb which executes the page-crawler.rb file above and works without the YPCrawler call, I get this error:
/lib/crawler/page-crawler.rb:23:in `block in <class:PageCrawler>': uninitialized constant YPCrawler::ListingCrawler (NameError)
The issue is on this line:
bizname = YPCrawler::ListingCrawler.new listing['id']
So how do I call that other from within my iterator in my page-crawler.rb?
Edit 1
When I just do `ListingCrawler.new listing['id'], I get the following error:
uninitialized constant YPCrawler::PageCrawler::ListingCrawler (NameError)
Edit 2
Here is the directory structure of my project:
Edit 3
My yp-crawler.rb looks like this:
require_relative "yp-crawler/version"
require_relative "crawler/page-crawler"
require_relative "crawler/listing-crawler"
module YPCrawler
end
In your yp-crawler.rb file, based on the structure that you posted, you should have something like:
require 'yp-crawler/version'
require 'crawler/listing-crawler'
require 'crawler/page-crawler'
Try this, in your yp-crawler.rb add the line:
Dir["#{File.dirname(__FILE__)}/crawler/**/*.rb"].each { |file| load(file) }
That should automatically include all files in your /crawler directory at runtime. Might want to do the same for the other directories.
Let me know if that helps :)
just learning ruby.
I have two folders inside my directory:
"lib" and "test"
Inside lib\person.rb:
class Person
attr_accessor :name
def introduction
"Hello, my name is #{name}!"
end
end
Inside test\test_person.rb:
require 'minitest/autorun'
require 'person'
class TestPerson < Minitest::Test
def test_introduction
person = Person.new
person.name = 'Bob'
assert(person.introduction == 'Hello, my name is Bob!')
end
end
When I try to run: ruby -I lib test/test_person.rb I get the following error:
(...) cannot load such file -- person (LoadError) (...)
The -I argument seems that is not working. I get the same error without it.
Any clue?
Tnks
Ok, just figure out what is going on...
I am Brazilian, and we have special characters for accents.
My folder name had one of this "ê".
Ruby is able to load the lib. But not able to recall it.
D:\OneDrive\Documentos\Documentos Felipe\Assuntos Acadêmicos>irb -I lib
irb(main):001:0> $:
=> ["D:/OneDrive/Documentos/Documentos Felipe/Assuntos Acad\x88micos/lib",(...)
\x88 = ê
Changed the folder name. Now it is ok.
If anyone knows how to solve this without worry about the name, would be helpful.
Tnks!
I have the following code (simplified):
decorator.rb
require 'decoratable'
class Decorator < SimpleDelegator
include Decoratable
end
decoratable.rb
require 'decorator_builder'
module Decoratable
def decorate(*decorators)
decorators.inject(DecoratorBuilder.new(self)) do |builder, decorator|
builder.public_send(decorator)
end.build
end
end
decorator_builder.rb
require 'rare_decorator'
class DecoratorBuilder
def initialize(card)
#card = card
#decorators = []
end
def rare
#decorators << ->(card) { RareDecorator.new(card) }
self
end
def build
#decorators.inject(#card) do |card, decorator|
decorator.call(card)
end
end
end
rare_decorator.rb
require 'decorator'
class RareDecorator < Decorator
# Stuff here
end
When I require decorator.rb, it causes RareDecorator to be declared before Decorator is declared, which is a problem since RareDecorator inherits from Decorator.
A possible solution is to split up decorator.rb like so:
class Decorator < SimpleDelegator; end
require 'decoratable'
class Decorator
include Decoratable
end
However, declaring dependencies in the middle of a file doesn't seem doesn't seem like a very clean solution to me.
Is there a better solution to this problem?
Instead of specifying requirements within every file, create one file which will require all the the application's requirements. Call it for example environment.rb:
require 'decoratable'
require 'decorator'
require 'decorator_builder'
require 'rare_decorator'
You don't need to worry about Decoratable not knowing what DecoratorBuilder is, as it is used within the method and the check for the constant will be executed when this method is called. Since you require decorator moment later, all will work.
I have three Ruby files in the same directory:
classthree.rb
otherclass.rb
samplecode.rb
Here are the contents of classthree.rb:
require './samplecode.rb'
require './otherclass.rb'
class ClassThree
def initialize()
puts "this class three here"
end
end
Here are the contents of samplecode.rb:
require './otherclass.rb'
require './classthree.rb'
class SampleCode
$smart = SampleCode.new
#sides = 3
##x = "333"
def ugly()
g = ClassThree.new
puts g
puts "monkey see"
end
def self.ugly()
s = SampleCode.new
s.ugly
puts s
puts $smart
puts "monkey see this self"
end
SampleCode.ugly
end
Here are the contents of otherclass.rb:
require './samplecode.rb'
require './classthree.rb'
END {
puts "ending"
}
BEGIN{
puts "beginning"
}
class OtherClass
def initialize()
s = SampleCode.new
s.ugly
end
end
My two questions are:
There has to be a better way than require './xyz.rb' for every class in the directory. Isn't there something like require './*.rb'?
When I run ruby otherclass.rb I get the following output:
Why do I get "beginning" and "ending" twice each??
At 1 - The best way to deal with it is to create another file. You can call it environment.rb or initialize.rb, and it would require all the needed files.
$LOAD_PATH.unshift File.dirname(__FILE__)
require 'samplecode.rb'
require 'classthree.rb'
require 'classthree.rb'
Now you only need to require this file once on the start of the application.
At 2 - You started from file 'otherclass.rb'. It displays the first 'beginning' bit and then it loads samplecode.rb file. At this point, 'otherclass.rb' has not been loaded yet - it was not required by any other file. hence samplecode.rb is rerunning whole otherclass.rb, which is being required there. Rerunning doesn't reload 'samplecode.rb' as it was already required (require checks first whether file was or was not required). That's why you're seeing those messages twice.
In my test app, which uses test::unit, I need to start by pulling a bunch of data from various sources. I'd like to only do this once - the data is only read, not written, and doesn't change between tests, and the loading (and error checking for the loading), takes some time.
There are values that I DO want reset every time, and those are easy enough, but what if I want persistant accessible values? What's the best way to do this?
I'm especially interested in solutions that would let my push those assignments to some module that can be included in all my tests, since they all need access to this data.
Why do you need it inside the test? You could define it gloabl:
gem 'test-unit'#, '>= 2.1.1' #startup
require 'test/unit'
GLOBAL_DATA = 11
class My_Tests < Test::Unit::TestCase
def test_1()
puts "Testing startup 1"
assert_equal(11, GLOBAL_DATA)
end
end
GLOBAL_DATA could be a (singleton)-class (respective an instance).
If you have only one testclass, you may use TestCase.startup:
gem 'test-unit'#, '>= 2.1.1' #startup
require 'test/unit'
class My_Tests < Test::Unit::TestCase
def self.startup
puts "Define global_data "
##global_data = 11
end
def test_1()
puts "Testing 1"
assert_equal(11, ##global_data = 11)
end
def test_2()
puts "Testing 2"
assert_equal(11, ##global_data = 11)
end
end
You can just put them at the top of the class. They will get executed, and then your tests will get executed.
You could do this in the setup method:
def setup
if !defined?(##initial_data)
# Whatever you need to do to get your initial data
##initial_data = foo
end
#other_data = bar
end