How can I get info from user with OptionParser in Ruby?

Question

For example, when I type ruby file.rb -a "water the plants" in command line I want this line to be added on a hash. Such as a to-do list. So it will look something like item1: water the plants Here's what I did so far:

require 'optparse'

option_parser = OptionParser.new do |opts|
    opts.on '-a', '--add', 
end          

Thanks in advance!

Answer 1

Look a bit more closely at the examples in the docs for OptionParser.

To accept a value for an argument, you have to specify it in the second argument to opts.on, something like this:

require 'optparse'
option_parser = OptionParser.new do |opts|
    opts.on '-a', '--add val' do |value|
      puts value
    end
end.parse!

To make it a required argument, just change that val to capitalized VAL (it can be any word, I'm just using "val" as an example).

Calling it, you can see how it works:

ruby file.rb -a "water the plants"
# => "water the plants"

ruby file.rb -a "water the plants" "do the dishes"
# => "water the plants"

ruby file.rb -a "water the plants" -a "do the dishes"
# => water the plants
# => do the dishes

As you can see, to pass multiple values, you need to include the -a flag multiple times. The block is called for each value individually.