Getting an error when using "require" in ruby - ruby

I just started Ruby. This is what I tried:
require'F:\RubymineProjects\practice122013\Coordinatev2'
class XYZCoordinate < Coordinate
attr_accessor :z
##newtotal=0
def initialize(x,y,z)
super(x,y)
#z=z
##newtotal+=1
end
def to_s
return "(##x, ##y, ##z)"
end
def XYZCoordinate.total
return "Number of 3D-coordinates are: ###newtotal"
end
end
p1=XYZCoordinate.new(0,0,0)
puts p1.to_s
p2=XYZCoordinate.new(1,5,5)
puts p2.to_s
puts XYZCoordinate.total
and this is the error I get:
C:\Ruby193\bin\ruby.exe -e $stdout.sync=true;$stderr.sync=true;load($0=ARGV.shift) F:/RubymineProjects/practice122013/XYZCoordinate.rb
F:/RubymineProjects/practice122013/XYZCoordinate.rb:3:in `<top (required)>': uninitialized constant Coordinate (NameError)
(0, 0)
from -e:1:in `load'
2
from -e:1:in `<main>'
3
Can anyone help me please.

This is what I did to correct the problem.
require"F:\\RubymineProjects\\practice122013\\Coordinatev2"
require"F:\\RubymineProjects\\practice122013\\Coordinate"
I had to specify where those 2 files were.

Related

undefined method 'execute' for nil:NilClass

I am making a tool in ruby which can interact with databases.
I am using amalgalite as an adapter for sqlite3.
Code:
require 'amalgalite'
# this is class RQuery
class RQuery
def db_open(db_name)
#db = Amalgalite::Database.new "#{db_name}.db"
make_class
end
def exec_this(query)
#db.execute(query)
end
def make_class
tables_list = exec_this("select name from sqlite_master where type='table'")
tables_list.each do |table|
#class_created = Object.const_set(table[0].capitalize, Class.new)
#class_created.class_eval do
define_singleton_method :first do
RQuery.new.exec_this("select * from #{table[0]} order by #{table[0]}.id ASC limit 1")
end
end
end
end
def eval_this(input)
instance_eval(input)
end
def code
print '>>'
input = gets
exit if input =~ /^q$/
puts eval_this(input)
code
end
end
Now when I am running the code everything works fine until I call table_name.first
It gives output
vbhv#fsociety ~/git/R-Query/bin $ ruby main.rb
Enter the code or q for quit
>>db_open('vbhv')
users
persons
people
programmers
>>Users.first
/home/vbhv/git/R-Query/lib/r-query.rb:36:in `instance_eval': undefined method `execute' for nil:NilClass (NoMethodError)
Did you mean? exec
from /home/vbhv/git/R-Query/lib/r-query.rb:29:in `block (3 levels) in make_class'
from (eval):1:in `eval_this'
from /home/vbhv/git/R-Query/lib/r-query.rb:36:in `instance_eval'
from /home/vbhv/git/R-Query/lib/r-query.rb:36:in `eval_this'
from /home/vbhv/git/R-Query/lib/r-query.rb:43:in `code'
from /home/vbhv/git/R-Query/lib/r-query.rb:44:in `code'
from /home/vbhv/git/R-Query/lib/r-query.rb:44:in `code'
from main.rb:4:in `<main>'
Now the 'execute' function it is talking about is inside amalgalite. What am I doing wrong here?? Thanks in Advance!
The problem in this was that the new class formed dynamically doesn't know about the connection variable '#db'. Hence the code solves the problem.
#class_created.instance_variable_set(:#database, #db)
A big thanks to Jagdeep Singh.

Celluloid 0.17.3 giving unexpected "undefined method" error

I have started using Celluloid gem this morning for that first time. I am following this Railscasts tutorial and trying to figure things out.
I have a class called "SomeClass" and it has only one method. Here is the code:
require 'celluloid'
class SomeClass
include Celluloid
def initialize(name)
#name = name
end
def assholify()
puts "#{#name} has become an ASSHOLE."
end
end
When I create new instances of the class and call its method (with a bang i.e. "assholify!"), I am getting the undefined method 'assholify!', error. But Celluloid is supposed to trigger the method asynchronously when it is called with a bang. So here is how I am calling the method:
names = ['John', 'Tom', 'Harry']
names.each do |name|
n = SomeClass.new name
n.assholify!
end
Here is the full backtrace of the error:
I, [2016-09-09T11:28:02.488618 #3682] INFO -- : Celluloid 0.17.3 is running in BACKPORTED mode. [ http://git.io/vJf3J ]
/home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/calls.rb:42:in `rescue in check': undefined method `assholify!' for #<SomeClass:0x10897dc> (NoMethodError)
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/calls.rb:39:in `check'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/calls.rb:26:in `dispatch'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/call/sync.rb:16:in `dispatch'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/cell.rb:50:in `block in dispatch'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/cell.rb:76:in `block in task'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/actor.rb:339:in `block in task'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/task.rb:44:in `block in initialize'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/task/fibered.rb:14:in `block in create'
from (celluloid):0:in `remote procedure call'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/call/sync.rb:45:in `value'
from /home/railsdev/.rvm/gems/ruby-2.3.1/gems/celluloid-0.17.3/lib/celluloid/proxy/sync.rb:22:in `method_missing'
from some_class.rb:18:in `block in <main>'
from some_class.rb:16:in `each'
from some_class.rb:16:in `<main>'
Why am I getting this error? Is it the right way to call the function? Also how do I get rid of Celluloid 0.17.3 is running in BACKPORTED mode. warning?
The undefined method error occurred because actor methods are not called with a bang in the recent versions of celluloid gem. Instead you call the method like this: n.async.assholify. So here is what the code should look like:
names = ['John', 'Tom', 'Harry']
names.each do |name|
n = SomeClass.new name
n.async.assholify # Instead of "n.assholify!"
end
For "Celluloid 0.17.0 is running in BACKPORTED mode" warning, take a look at this wiki. Backported Mode is the default, for a limited time. If you use require 'celluloid/current' instead of require 'celluloid', you should not see this warning.

Why is Ruby seeing `A.run` in class B as a constant and not a class?

so this is my first question on stack overflow and I am new to Ruby, so if this is a simple question, please be nice.
I am starting off in OOP and making a game. What I think is wrong is that Ruby is thinking that a different class is a constant in the current class.
Here is my code:
./a.rb
require "./b"
class A
class << self
def run
puts "A ran."
end
end
end
./b.rb
class B
require './a'
def test
A.run
end
end
b = B.new
b.test
When I run ruby b.rb, I get:
/Users/alexstriff/Dropbox/Code/ruby/ex45/b.rb:5:in `test': uninitialized constant B::A (NameError)
from /Users/alexstriff/Dropbox/Code/ruby/ex45/b.rb:11:in `<top (required)>'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:45:in `require'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:45:in `require'
from /Users/alexstriff/Dropbox/Code/ruby/ex45/a.rb:1:in `<top (required)>'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:45:in `require'
from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:45:in `require'
from b.rb:2:in `<class:B>'
from b.rb:1:in `<main>'
So why is A.run seen as a constant by class B, instead of as a class?
Edit:
Could it possibly be a problem with the 'circular require'? I ran this under ruby -w and that came up.
Yes, as you mentioned in your edit, I believe your issue is with a circular require. As you can see, when you run ruby b.rb, you require a.rb, which then requires b.rb again, etc. Instead, I would advise removing the require in a.rb, as it does not seem to depend on b.rb.
As a separate issue, I think the error you are getting is because you don't specify that A is a top-level class. Also, having the require inside of class B does not make A accessible inside B, so I would move it outside instead:
require './a'
class B
def test
::A.run
end
end
b = B.new
b.test

Error while upgrading from Rails 3.1 to Rails 3.2

Upgrade steps were performed as mentioned in http://guides.rubyonrails.org/3_2_release_notes.html
Right now I'm on Ruby 1.8.7 and Rails 3.1.x (using system ruby). I installed RVM with ruby 1.8.7 and added to rails 3.2 and then I get the following error:
[app]$ rails console
Faraday: you may want to install system_timer for reliable timeouts
$HOME/src/qbol/tapp/config/environment.rb:16:in `add': undefined method `>' for nil:NilClass (NoMethodError)
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/tagged_logging.rb:55:in `add'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/tagged_logging.rb:61:in `info'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activerecord-3.2.17/lib/active_record/railtie.rb:86
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/lazy_load_hooks.rb:36:in `instance_eval'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/lazy_load_hooks.rb:26:in `on_load'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/lazy_load_hooks.rb:25:in `each'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/lazy_load_hooks.rb:25:in `on_load'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activerecord-3.2.17/lib/active_record/railtie.rb:80
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/initializable.rb:30:in `instance_exec'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/initializable.rb:30:in `run'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/initializable.rb:55:in `run_initializers'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/initializable.rb:54:in `each'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/initializable.rb:54:in `run_initializers'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/application.rb:136:in `initialize!'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/railtie/configurable.rb:30:in `send'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/railtie/configurable.rb:30:in `method_missing'
from $HOME/src/app/config/environment.rb:48
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/dependencies.rb:251:in `require'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/dependencies.rb:251:in `require'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/dependencies.rb:236:in `load_dependency'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/activesupport-3.2.17/lib/active_support/dependencies.rb:251:in `require'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/application.rb:103:in `require_environment!'
from $HOME/.rvm/gems/ruby-1.8.7-p374/gems/railties-3.2.17/lib/rails/commands.rb:40
from script/rails:6:in `require'
from script/rails:6
This is on my development box. Any idea why this is happening?
EDIT: Below is the environment.rb. The error is happening on the last line App::Application.initialize!
# Load the rails application
require File.expand_path('../application', __FILE__)
module ActiveSupport
class BufferedLogger
def self.current_user
Thread.current[:user]
end
def self.current_user=(user)
Thread.current[:user] = user
end
def add(severity, message = nil, progname = nil, &block)
return if #level > severity
message = (message || (block && block.call) || progname).to_s
level = {
0 => "DEBUG",
1 => "INFO ",
2 => "WARN ",
3 => "ERROR",
4 => "FATAL"
}[severity] || "UNKNOWN"
user=BufferedLogger.current_user
if(!user.nil?)
idstr = "uid:#{user.id}"
if !user.current_app_user.nil?
idstr.concat(", acid: #{user.current_app_user.account_id}")
end
else
idstr=""
end
message = "[%s: %s #{idstr}] %s" %
["#{level} pid: #{$$}", Time.now.strftime("%y-%m-%d %H:%M:%S"), message]
message = "#{message}\n" unless message[-1] == ?\n
buffer << message
auto_flush
message
end
end
end
# Initialize the rails application
App::Application.initialize!
The error is happening inside ActiveSupport::BufferedLogger#add method call and you appear to be monkey-patching this class. The internals of ActiveSupport::BufferedLogger have likely changing between the versions of Rails you're using.
Try removing all of the ActiveSupport::BufferedLogger code from your environment.rb to work past this error and get your app running. Then, if you still need the monkeypatch (don't know why), you'd have to rewrite it on top of the newer version of the class.

Undefined method each in Ruby Regexp task

I have series of zip files under #workingdir, and am trying to unzip the files that match #Regexp, and print the lines from them.
require 'zip/zip'
#workingdir = '/my/dir/structure/*.zip'
#Regexp = '/yup:maybe.*nope/i'
Dir.glob(#workingdir) do |zips|
Zip::ZipFile.open(zips) do |file|
file.each do |search|
tempFile = file.read(search)
tempFile.each do |line|
if (line =~ #Regexp ) then
p line
end
end
end
end
end
Below is the error message from IRB:
NoMethodError: undefined method `each' for #<String:0x0000000168bf40>
from (irb):70:in `block (3 levels) in irb_binding'
from /var/lib/gems/1.9.1/gems/rubyzip2-2.0.2/lib/zip/zip.rb:1122:in `each'
from /var/lib/gems/1.9.1/gems/rubyzip2-2.0.2/lib/zip/zip.rb:1122:in `each'
from /var/lib/gems/1.9.1/gems/rubyzip2-2.0.2/lib/zip/zip.rb:1265:in `each'
from (irb):68:in `block (2 levels) in irb_binding'
from /var/lib/gems/1.9.1/gems/rubyzip2-2.0.2/lib/zip/zip.rb:1381:in `open'
from (irb):67:in `block in irb_binding'
from (irb):66:in `glob'
from (irb):66
from /usr/bin/irb:12:in `<main>'
I tried tempFile.grep, and received the same error, except that grep was an undefined method. I believe I need to define a class.
Turns out my code had two problems. 1) My regular expression was being processed as a string (I should not have used the quotes). 2) Seeing as it runs fine otherwise on Ruby 1.8.7, I suspect the is a difference in how 1.8.7 and 1.9.1 process the 'each' method. If anyone has additional insights, I'm more than happy to hear them. The code below works fine on 1.8.7:
require 'zip/zip'
#workingdir = '/my/dir/structure/*.zip'
#Regexp = /regexp/i
Dir.glob(#workingdir) do |zips|
Zip::ZipFile.open(zips) do |file|
file.each do |search|
tempFile = file.read(search)
tempFile.each do |line|
if (line =~ #Regexp) then
puts zips + ': ' + line.chomp
end
end
end
end
end
Thanks again everyone!

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