Neither Ruby and Nor Irb Can Load .Rb File in Current Directory

How would I have irb require the config/boot.rb file from the directory I run irb in?

I would do:

 config_file = File.join(Dir.pwd, 'config', 'boot.rb')
 require config_file if File.exist?(config_file)

Why isn't current directory on my Ruby path?

In Ruby 1.9.2 the Powers that Be introduced an explicit change so that the working directory is no longer in the Ruby path. I thought it was the Apocalypse and a terrible thing, until I learned about require_relative. My apps tend to look like this:

require 'some_gem'
require 'another_gem'
require_relative 'lib/init'

And then lib/init.rb can have:

require_relative 'lib1' # this is lib/lib1.rb
require_relative 'lib2' # this is lib/lib2.rb

It's the bees knees, and solves all sorts of problems I used to have with requiring the same file from different working directories.

Edit: Unfortunately (for reasons I don't know and haven't looked into) require_relative doesn't work specifically in irb. For this you can:

1. do what you initially described: either $: << '.' or $:.unshift '.', or

2. you can use load 'myfile.rb' or require './myfile' instead:

   irb(main):001:0> Dir['*.rb']
   => ["a.rb", "bar.rb", "foo.rb", "prime.rb", "tmp.rb"]
   
   irb(main):002:0> require 'a'
   LoadError: no such file to load -- a
     from <internal:lib/rubygems/custom_require>:29:in `require'
     from <internal:lib/rubygems/custom_require>:29:in `require'
     from (irb):2
     from /usr/local/bin/irb:12:in `<main>'
   
   irb(main):003:0> require_relative 'a'
   LoadError: cannot infer basepath
     from (irb):3:in `require_relative'
     from (irb):3
     from /usr/local/bin/irb:12:in `<main>'
   
   irb(main):004:0> load 'a.rb'
   a
   => true
   
   irb(main):005:0> require './a'
   a
   => true
   

Strange irb behaviour, listing content current directory

The following line will have tab characters in it:

        raise StandardError

irb uses readline which means that the tab key is used for tab completion. Double tab will show you all the available options.

To see this in action, just launch irb and hit the tab key twice.

See https://superuser.com/questions/37148/how-to-disable-double-tab-to-show-available-commands-in-linux-console for guidance on how to disable it.

Can you 'require' ruby file in irb session, automatically, on every command?

I usually create a simple function like this:

def reload
    load 'myscript.rb'
    # Load any other necessary files here ...
end

With that, a simple reload will re-import all of the scripts that I'm working on. It's not automatic, but it's the closest thing that I've been able to come up with.

You may be able to override method_missing to call this function automatically when your object is invoked with a method that doesn't exist. I've never tried it myself, though, so I can't give any specific advice. It also wouldn't help if you're calling a method that already exists but has simply been modified.

In my own laziness, I've gone as far as mapping one of the programmable buttons on my mouse to the key sequence "reload<enter>". When I'm using irb, all it takes is the twitch of a pinky finger to reload everything. Consequently when I'm not using irb, I end up with the string "reload" inserted in documents unintentionally (but that's a different problem entirely).

Rspec Ruby Basic Example Error

This is a great simple example to get started with rspec. To make everything work do the following:

1. Place your bowling.rb file in
   lib/bowling.rb.
2. Place your bowling_spec.rb file in
   spec/bowling_spec.rb.
3. Run the command rspec
spec/bowling_spec.rb if you are using rpsec 2.
4. Run the command spec spec/bowling_spec.rb if you are using rspec 1.

Also, an updated example can be found here.

How to load a ruby file in to IRB?

From the require docs:

Any constants or globals within the loaded source file will be available in the calling program’s global namespace. However, local variables will not be propagated to the loading environment.

So if in options.rb you have something like:

key = something

(i.e. key is a local in the file) then it will not be available in irb. If you make it a global (e.g. $key = 'something') or a constant (e.g. KEY = 'something') it should be available.

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