Access an instance variable without using the @ sign

Question

Here is an example from a book: ``` class TextCompressor attr_reader :unique, :index def initialize( text ) @unique = [] @index = [] add_text( text ) end def add_text( text ) words = text.split words.each { |word| add_word( word ) } end def add_word( word ) i = unique_index_of( word ) || add_unique_word( word ) @index << i end def unique_index_of( word ) @unique.index(word) end def add_unique_word( word ) @unique << word unique.size - 1 end end ``` In the method `add_unique_word` the author access the variable `unique` without using the @ sign (`unique.size - 1`). How is it possible, and why it is so?

Accepted Answer

This line `attr_reader :unique, :index` created a `getter` for the attribute:

```
def unique
 @unique
end
```

what you see in the line `unique.size - 1` is a method call to the getter, then accesing the `size` property of it.

Access an instance variable without using the @ sign

Solution

Problem