Ruby: Print Version
Print version from the command line:
ruby -v
Print version from within a script:
# Ruby p RUBY_VERSION # "3.1.2"
Printing version from script is a important technique to find out which
version your script is running. Because, you might have several version
installed, and and it's harder to find out in terminal,
because there are aliases, links, path environment
variables, etc effect which Ruby version will
start when you type ruby
in shell.