I am writing a program which includes two file. I’m the first file all I am doing is initializing the next file which includes multiple classes. I call the class at the bottom of the file, but it runs the class at the top of the file.
Btw I am running ruby
First file:
Require ‘./secondfile.rb’
newfile.Lastclass
Second file:
class Firstclass
end
class Lastclass
end
Hint #1. It's better to write without .
It depends on directory from where you run your app.
For example you have directory folder. And there you have two files:
file.rb
puts "I'm file.rb"
main.rb
require './file.rb'
If you run your app from folder - it's ok:
folder$ ruby main.rb
I'm file.rb
But if you'll run it from high level - it will be error:
folder$ cd ..
:~$ ruby folder/main.rb
kernel_require.rb:55:in `require': cannot load such file -- ./file.rb (LoadError)
But how to write in this case?
Hint #2. You can use special method
main.rb
require "./#{__dir__}/file.rb"
Now it's ok in all cases:
~$ ruby folder/main.rb
I'm file.rb
folder$ ruby main.rb
I'm file.rb
But you can write it better.
Hint #3. You can use require_relative
main.rb
require_relative 'file.rb'
And even better.
main.rb
require_relative 'file'
Ruby understand it.
~$ ruby folder/main.rb
I'm file.rb
folder$ ruby main.rb
I'm file.rb
Hope this helps you.
Classes are injected into the root namespace if they're defined. If another file defines a class, all files get it:
require_relative './secondfile.rb'
Lastclass
This is unlike JavaScript (e.g. Node.js) where you must explicitly import classes from other files. In Ruby it happens by manipulating the root namespace.
Another note is to pay close attention to which slashes you use. In your code you used a backslash, which is incorrect. You also used the wrong quotes. Often every character counts when programming.
I'm working in an IRB shell on a dos CMD
I load a module from a mystuff file
require '.\mystuff'
I change the module in the mystuff file and I type again
require '.\mystuff'
How come the IRB does not pick up the changes in the file when I try to call functions or variables from the newest version of my mystuff module?
require will not load the same file twice. If you want to load the file again, you need to use load. See What is the difference between include and require in Ruby? for more information.
Your Syntax is Wrong
Ruby doesn't use backslashes. You need to use forward slashes, or use File#join.
Your $LOAD_PATH is Wrong
Your $LOAD_PATH (a.k.a $:) is wrong. You need to include the present working directory with:
$: << '.'
in irb, or use Kernel#require_relative in executable or sourced files.
I am currently in
Dropbox/96_2013/work/ror/dmc/dmStaffing/QA/selenium_server_wyatt/spec/2day/units/
I can go into irb and require a file but it's a really long require...
require '/home/durrantm/Dropbox/96_2013/work/ror/dmc/dmStaffing/QA/selenium_server_wyatt/spec/2day/units/login_as_admin_spec.rb'
=> true
I want to use require_relative, as in
$ cd /home/durrantm/Dropbox/96_2013/work/ror/dmc/dmStaffing/QA/selenium_server_wyatt/spec/2day/
$ pwd
/home/durrantm/Dropbox/96_2013/work/ror/dmc/dmStaffing/QA/selenium_server_wyatt/spec/2day
$ irb
irb(main):001:0> require_relative 'units/login_as_admin_spec.rb'
but I get:
LoadError: cannot infer basepath
require_relative requires a file relative to the file the call to require_relative is in. Your call to require_relative isn't in any file, it's in the interactive interpreter, therefore it doesn't work.
You can use the long form of require by explicitly passing the full path:
require './units/login_as_admin_spec.rb'
Or you add the current directory to the $LOAD_PATH and just require as usual:
$LOAD_PATH << '.'
require 'units/login_as_admin_spec'
This is a known bug in ruby:
Ruby bug #4487: require_relative fails in an eval'ed file
If you are using Pry, instead of IRB, this can be fixed by installing the pry-require_relative gem.
gem install pry-require_relative
This worked:
require File.expand_path("../login_as_admin_spec.rb", __FILE__)
require_relative works in the context of the current source file. This is different than the current working directory. I don't believe irb or pry have an understanding of "this current source file" concept; since you're not actually in a file.
In these REPLs, just use a relative path reference require './units/login_as_admin_spec.rb'.
How exactly does the require command in Ruby work? I tested it with the following two files that are in the same directory.
test.rb
require 'requirements'
square(2)
requirements.rb
def square(x)
x*x
end
But when I run ruby test.rb while I'm in the same directory as the files "test.rb" and "requirements.rb", I get the error:
/usr/local/rvm/rubies/ruby-1.9.3-p286/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- requirements (LoadError)
from /usr/local/rvm/rubies/ruby-1.9.3-p286/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from test.rb:1:in `<main>'
which I think means it can't find the requirements.rb file. But it's in the same directory as test.rb! How does one fix this?
Much thanks in advance. I apologize for such noob questions.
IIRC, ruby 1.9 doesn't include current dir ('.') to LOAD_PATH. You can do one of these:
# specify relative path
require './test1'
# use relative method
require_relative 'test1'
# add current dir to LOAD_PATH
$LOAD_PATH.unshift '.'
require 'test1'
I too just started to learn how ruby works, so I'm not perfectly sure if this helps. But try require_relative instead of require and I think it will work.
Afaik require searches in the ruby libary.
I've one file, main.rb with the following content:
require "tokenizer.rb"
The tokenizer.rb file is in the same directory and its content is:
class Tokenizer
def self.tokenize(string)
return string.split(" ")
end
end
If i try to run main.rb I get the following error:
C:\Documents and Settings\my\src\folder>ruby main.rb
C:/Ruby193/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- tokenizer.rb (LoadError)
from C:/Ruby193/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require '
from main.rb:1:in `<main>'
I just noticed that if I use load instead of require everything works fine. What may the problem be here?
I just tried and it works with require "./tokenizer".
Just do this:
require_relative 'tokenizer'
If you put this in a Ruby file that is in the same directory as tokenizer.rb, it will work fine no matter what your current working directory (CWD) is.
Explanation of why this is the best way
The other answers claim you should use require './tokenizer', but that is the wrong answer, because it will only work if you run your Ruby process in the same directory that tokenizer.rb is in. Pretty much the only reason to consider using require like that would be if you need to support Ruby 1.8, which doesn't have require_relative.
The require './tokenizer' answer might work for you today, but it unnecessarily limits the ways in which you can run your Ruby code. Tomorrow, if you want to move your files to a different directory, or just want to start your Ruby process from a different directory, you'll have to rethink all of those require statements.
Using require to access files that are on the load path is a fine thing and Ruby gems do it all the time. But you shouldn't start the argument to require with a . unless you are doing something very special and know what you are doing.
When you write code that makes assumptions about its environment, you should think carefully about what assumptions to make. In this case, there are up to three different ways to require the tokenizer file, and each makes a different assumption:
require_relative 'path/to/tokenizer': Assumes that the relative path between the two Ruby source files will stay the same.
require 'path/to/tokenizer': Assumes that path/to/tokenizer is inside one of the directories on the load path ($LOAD_PATH). This generally requires extra setup, since you have to add something to the load path.
require './path/to/tokenizer': Assumes that the relative path from the Ruby process's current working directory to tokenizer.rb is going to stay the same.
I think that for most people and most situations, the assumptions made in options #1 and #2 are more likely to hold true over time.
Ruby 1.9 has removed the current directory from the load path, and so you will need to do a relative require on this file, as David Grayson says:
require_relative 'tokenizer'
There's no need to suffix it with .rb, as Ruby's smart enough to know that's what you mean anyway.
require loads a file from the $LOAD_PATH. If you want to require a file relative to the currently executing file instead of from the $LOAD_PATH, use require_relative.
I would recommend,
load './tokenizer.rb'
Given, that you know the file is in the same working directory.
If you're trying to require it relative to the file, you can use
require_relative 'tokenizer'
I hope this helps.
Another nice little method is to include the current directory in your load path with
$:.unshift('.')
You could push it onto the $: ($LOAD_PATH) array but unshift will force it to load your current working directory before the rest of the load path.
Once you've added your current directory in your load path you don't need to keep specifying
require './tokenizer'
and can just go back to using
require 'tokenizer'
This will work nicely if it is in a gem lib directory and this is the tokenizer.rb
require_relative 'tokenizer/main'
For those who are absolutely sure their relative path is correct, my problem was that my files did not have the .rb extension! (Even though I used RubyMine to create the files and selected that they were Ruby files on creation.)
Double check the file extensions on your file!
What about including the current directory in the search path?
ruby -I. main.rb
I used jruby-1.7.4 to compile my ruby code.
require 'roman-numerals.rb'
is the code which threw the below error.
LoadError: no such file to load -- roman-numerals
require at org/jruby/RubyKernel.java:1054
require at /Users/amanoharan/.rvm/rubies/jruby-1.7.4/lib/ruby/shared/rubygems/custom_require.rb:36
(root) at /Users/amanoharan/Documents/Aptana Studio 3 Workspace/RubyApplication/RubyApplication1/Ruby2.rb:2
I removed rb from require and gave
require 'roman-numerals'
It worked fine.
The problem is that require does not load from the current directory. This is what I thought, too but then I found this thread. For example I tried the following code:
irb> f = File.new('blabla.rb')
=> #<File:blabla.rb>
irb> f.read
=> "class Tokenizer\n def self.tokenize(string)\n return string.split(
\" \")\n end\nend\n"
irb> require f
LoadError: cannot load such file -- blabla.rb
from D:/dev/Ruby193/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `req
uire'
from D:/dev/Ruby193/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `req
uire'
from (irb):24
from D:/dev/Ruby193/bin/irb:12:in `<main>'
As it can be seen it read the file ok, but I could not require it (the path was not recognized). and here goes code that works:
irb f = File.new('D://blabla.rb')
=> #<File:D://blabla.rb>
irb f.read
=> "class Tokenizer\n def self.tokenize(string)\n return string.split(
\" \")\n end\nend\n"
irb> require f
=> true
As you can see if you specify the full path the file loads correctly.
First :
$ sudo gem install colored2
And,you should input your password
Then :
$ sudo gem update --system
Appear
Updating rubygems-update
ERROR: While executing gem ... (OpenSSL::SSL::SSLError)
hostname "gems.ruby-china.org" does not match the server certificate
Then:
$ rvm -v
$ rvm get head
Last
What language do you want to use?? [ Swift / ObjC ]
ObjC
Would you like to include a demo application with your library? [ Yes / No ]
Yes
Which testing frameworks will you use? [ Specta / Kiwi / None ]
None
Would you like to do view based testing? [ Yes / No ]
No
What is your class prefix?
XMG
Running pod install on your new library.
you need to give the path.
Atleast you should give the path from the current directory. It will work for sure.
./filename