Type Conversion

Introduction

We can represent the number 2 in ruby in a variety of different formats:

• 2
• 2.0
• "2"

Though it may seem strange to represent 2 as a String, we often find use cases for this, such as:

Define a method, #time_string that accepts 3 arguments: hours, minutes, and seconds (all integers). Convert these integers into one contiguous time string that has the following format:

    "hh:mm:ss"

Well.. if we use simple interpolation:

    "#{hours}:#{minutes}:#{seconds}"

We might end up with something like this:

    "12:1:3"

And this doesn't have the appropriate format! We need something like:

    "12:01:03"

To aid us in this challenge, we can use type conversion. Don't worry about solving the above problem now, we'll do it in the exercises!

#to_?

All three objects: Fixnums, Floats, and Strings have methods that allow us to convert between the types.

For example, if I want to convert from a String to a Fixnum, I could use the #to_i method.

  int = "5".to_i
  puts int # ==> 5

We can actually convert to/from any and all of the aforementioned classes.

  5.to_s      # ==> "5"
  5.to_f      # ==> 5.0

  5.3.to_i    # ==> 5
  5.3.to_s    # ==> "5.3"

  "5.6".to_i  # ==> 5
  "5.6".to_f  # ==> 5.6

Test these in pry!