The last tool you need is a Ruby runtime. This is a program that can execute
Ruby code, and it is a program that can be run in your shell (much like
If you have some code in a file with the name
hello.rb, and you have
navigated to the directory where the file is saved, then you can type the
following and hit enter, in order to execute the code:
This will tell the
ruby runtime to interpret the contents of the file
hello.rb as Ruby code, and execute it.
One can also use this program to do other things. You probably won’t need these a lot, but we think it’s good to know. You can try these by typing these commands in your terminal.
E.g. you can print out the version of the program:
Or execute Ruby code without storing it to a file:
ruby -e 'puts 123'