How to load a ruby file in to IRB?

Question

I have a file: options.rb I open IRB and type:

require './options.rb'
 #=> true

Try to call a variable in the options file such as key (yes this variable is there and the file is saved)

NameError: undefined local variable or method `key' for main:Object
from (irb):2

Why is this not working? By the way also tried to load the file as: irb -r ./options.rb

UPDATE

Also tried to do load './options.rb' which does return #=> true but this also does not work.

Answer 1

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

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

Answer 2

If you do not like global variables (as matt suggested) you might also make it an instance variable of the object irb is running on (an instance of Object available through self as ruby always has an object it is operating on) you may also assign

@key='value'

in your file which will give you access to @key in your irb -session afterwards. This will work with either require as with load , but require will only load the file if it has not already done so while load will always execute the code in the file and thus will end up overwriting the contents of your variable if it has been changed in the mean time.

Answer 3

Ruby is a interpreted language, so for the interpreter to notice your declarations you need to actually 'run' them, the corresponding command in irb is

load './options.rb'