A for-fun vaguely Elixir-style guard clause proof-of-concept in Ruby. Probably not a good idea… https://twitter.com/henrik/status/1570145637920026624

ruby_guard_clause_proof_of_concept.rb

class Object
  def guard(cond, meth)
    prepend(Module.new {
      define_method(meth) { |*a, **aa, &b|
        super(*a, **aa, &b) if send(cond, *a, *aa, &b)
      }
    })
  end
end

class Foo
  guard :even?,
  def hi(number)
    puts "Hi #{number}!"
  end

  private

  def even?(num) = num.even?
end

Foo.new.hi(1)  # No output.
Foo.new.hi(2)  # Output.