Learn to Program, 2nd Edition

Conversions

To get the string version of an object, we simply write .to_s after it:

var1 =  2
var2 = '5'
puts var1.to_s + var2

25

Similarly, .to_i gives the integer version of an object, and .to_f gives the float version. Let’s look at what these three methods do (and don’t do) a little more closely:

var1 =  2
var2 = '5'
puts var1.to_s + var2
puts var1 + var2.to_i

25
7

Notice that, even after we got the string version of var1 by calling to_s, var1 was always pointing at 2 and never at '2'. Unless we explicitly reassign var1 (which requires an = sign), it will point at 2 for the life of the program.

Now let’s try some more interesting (and a few just weird) conversions:

puts '15'.to_f
puts '99.999'.to_f
puts '99.999'.to_i
puts  ...