The Book of Ruby

Symbols and Variables

To understand the relationship between a symbol and an identifier such as a variable name, take a look at the symbols_2.rb program. It begins by assigning the value 1 to a local variable, x. It then assigns the symbol :x to a local variable, xsymbol:

symbols_2.rb

x = 1
xsymbol = :x

At this point, there is no obvious connection between the variable x and the symbol :x. I have declared a method that simply takes some incoming argument and inspects and displays it using the p method. I can call this method with the variable and the symbol:

def amethod( somearg )
    p( somearg )
end

# Test 1
amethod( x )
amethod( :x )

This is the data that the method prints as a result:

1
:x

In other words, the value of the x variable is 1, since that’s ...