Learn Ruby the Hard Way: A Simple and Idiomatic Introduction to the Imaginative World of Computational Thinking with Code, Third Edition

Exercise 13. Parameters, Unpacking, Variables

In this exercise we will cover one more input method you can use to pass variables to a script (script being another name for your .rb files). You know how you type ruby ex13.rb to run the ex13.rb file? Well, the ex13.rb part of the command is called an “argument.” What we’ll do now is write a script that also accepts arguments.

Type this program, and I’ll explain it in detail:

ex13.rb

Click here to view code image

 1    first, second, third = ARGV  2  3    puts "Your first variable is: #{first}"  4    puts "Your second variable is: #{second}"  5    puts "Your third variable is: #{third}"

ARGV is the “argument variable,” a very standard name in programming, that you will find used in many other languages. ...