lol_ruby.rb

require 'delegate'

class LolRuby < SimpleDelegator
  def +(x)
    __getobj__ + (x * 10)
  end
end

def add_one(x)
  x + 1
end

add_one(LolRuby.new(1)) # => 11
add_one(1) # => 2

types.go

package main

import "fmt"

func AddOne(x int) int {
    return x + 1
}

func main() {
    // fmt.Println(AddOne("lol")) // Won't even compile
    fmt.Println(AddOne(10))
}