Ruby Command Line Arguments

In your ruby programs you can access any command line arguments passed by the shell with the argv special variable argv is an array variable which holds as strings each argument passed by the shell.

Ruby command line arguments.

2 getting the value of the ruby command line args. How to start a development server. The rubygems environment can be controlled through command line arguments gemrc files environment variables and built in defaults. The rails command lineafter reading this guide you will know.

Check out statuscode weekly our language and architecture agnostic newsletter that covers the biggest news across the entire software development world. Using command line arguments. How to generate models controllers database migrations and unit tests. To work with the actual values of the arguments that are passed into your ruby program just treat argv as a normal ruby array and get the values like this.

How to create a rails application. You re not just a rubyist you re a software developer right. Our input file should be the first command line arg input file argv 0 our output file should be the second command line arg. Optionparser has a number of features that make it quite appealing to ruby programmers.

Using command line arguments adds a new tool to your ruby toolbelt which you can use to get user input into your program if you choose. The interpreter can be invoked with any of the following options to control the environment and behavior of the interpreter. Ruby is generally run from the command line in the following way ruby options programfile arguments. How to experiment with objects through an interactive shell.

Ruby comes equipped with a powerful and flexible tool to parse command line options optionparser. When written inside your ruby program argv will take take a command line command that looks like this. Once you learn how to use this you ll never go back to looking through argv manually. Ruby captures command line arguments with a special array named argv.