Contents
How can I run a script in Ruby?
If you get tired of typing ruby in front of the file, you can tell your computer what to do instead. Just let it know that the file is executable and specify that Ruby should be used to run it. This takes 2 steps: Use the chmod command to declare the file executable. Just type $ chmod + x your_filename. rb once and you’ll be able to execute it.
What does argv stand for in Ruby script?
ARGV is simply an array that contains all your command line arguments: As you can see in the last example above, you can only pass in command line arguments from the actual command line (not within IRB). There are a few other special constants you can access from within your script:
What does$ 0 mean in Ruby script?
$0 is the main or original file that was run (which could be different from your script if your script had just been require d by that original file). $ (aka $LOAD_PATH) is an array that contains the “load path”, or all the directories the interpreter searches through when it needs to find a file.
How to run a Ruby script in Sublime Text?
For example, if you are using Sublime Text, you can run the currently open file simply by using the command CMD + B (Mac) to “build” the file. A little window will pop up at the bottom which displays the results as if you had typed $ ruby your_file. rb on the command line.
Which is the first line in a Ruby script?
The shebang line is already done for you; it’s the first line in the script starting with #!. This tells the shell what type of file this is. In this case, it’s a Ruby file to be executed with the Ruby interpreter. To mark the file as executable, run the command chmod +x test.rb.
What can you do with the Ruby prompt?
The interactive Ruby prompt provides an interface to the Ruby language for instant experimentation. This comes in handy while learning Ruby and experimenting with things like regular expressions. Ruby statements can be run and the output and return values can be examined immediately.
How to execute command in subshell in Ruby?
Executes the given command in a subshell. Returns true if the command was found and run successfully, false otherwise. Replaces the current process by running the given external command. Returns none, the current process is replaced and never continues.
How to declare a file as executable in Ruby?
Use the chmod command to declare the file executable. Just type $ chmod + x your_filename. rb once and you’ll be able to execute it. This may not even be necessary depending on your current file permissions.
How do you enter a command in Ruby?
To enter a command all you need to do is type in the command and hit the enter key. The first command to learn is the cd command, which will be used to get to the directory where you keep your Ruby files. The command below will change directory to the \\scripts directory.
How to include a Ruby script in an IRB session?
If you want to include a gem file (a library of methods, for instance) or another Ruby script in your IRB session, use require. require will search for any gems you’ve downloaded from the internet. If you’ve explicitly provided a path to be required, for instance ./ my_script. rb, it will bring in that specific file instead.