In JavaScript I could do this:

var someObject = {
    bar: "Hello, world"
};
foo="bar";
console.log (someObject[foo]);

And the console would show me "Hello world"

How do I do this in ruby?

#This does not work:
@someObject.bar="Hello, world" #@someObject holds a class
foo="bar"
puts @someObject[foo]

This is driving me nuts!

I have googled. Alot. None of the possible variations I could think of with "Ruby accessing object attributes with variable" and "Accessing a variable of an object using dynamic value in ruby" gave any results. What do you call this?

It seems like you want Hash.

someObject = {bar: "Hello, world!"}  # symbol
foo = :bar
someObject[foo]
# => "Hello, world!"

anotherObject = {"bar" => "Hello, another world!"}  # string
foo = "bar"
anotherObject[foo]
# => "Hello, another world!"

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