irb

irb.rb

irb(main):001:> why_are_we_here = -> (x) { puts x }
irb(main):002:> why_are_we_here.call("It's worth it.")
It\'s worth it.
=> nil
irb(main):003:> why_are_we_here = -> (x) { why_are_we_here(x) }
irb(main):004:> why_are_we_here.call(nil)

Traceback (most recent call last):
        5: from /usr/bin/irb:23:in `<main>'
4: from /usr/bin/irb:23:in `load'
        3: from /usr/lib/ruby/gems/2.7.0/gems/irb-1.2.1/exe/irb:11:in `<top (required)>'
        2: from (irb):8
        1: from (irb):7:in `block in irb_binding'
IRB::NoSuchJob (No such job().)