The Algebra of Loans in Rust(nadrieril.github.io)

  #!/usr/bin/env python3
  import inspect
  
  def frobnicate(unfrobbed: any) -> None:
      frame = inspect.currentframe().f_back
      for name in [name for name, value in frame.f_locals.items() if value is unfrobbed]:
          del frame.f_locals[name]
      for name in [name for name, value in frame.f_globals.items() if value is unfrobbed]:
          del frame.f_globals[name]
  
  foo = open("bar.txt")
  answer = frobnicate(foo)
  print(foo)

  
  Traceback (most recent call last):
    File "hackers.py", line 20, in <module>
      print(foo)
            ^^^
  NameError: name 'foo' is not defined

  #include <print>
  
  struct Object
  {
      char member{'a'};
  };
  
  void assign_pointer(Object *ptr)
  {
      Object replacement{'b'};
      ptr = &replacement;
  }
  
  void assign_reference(Object &ref)
  {
      Object replacement{'b'};
      ref = replacement;
  }
  
  int main()
  {
      Object obj{};
      std::println("Original value: {}", obj.member);
      assign_pointer(&obj);
      std::println("After assign_pointer: {}", obj.member);
      assign_reference(obj);
      std::println("After assign_reference: {}", obj.member);
      return 0;
  }

  $ ./a.out
  Original value: a
  After assign_pointer: a
  After assign_reference: b