.. efun:: mixed copy(mixed value)

  Create a shallow copy of :arg:`value` and return it. For arrays and mappings this means that a new array or mapping is created with copies of the original content. Embedded arrays and mappings are copied by reference!

  For other values this function is a no-op.

  .. usage::

    Because the example below uses a shallow copy, modifications to the nested array are visible in both copies::

      mixed *a, *b;

      a = ({ 1, ({ 21, 22 }) });
      b = copy(a);
      a[0] = -1;
      a[1][0] = -21;

      // a is now ({ -1, ({ -21, 22 }) })
      // b is now ({  1, ({ -21, 22 }) })

  :history 3.2.6 introduced:

  .. seealso:: :efun:`deep_copy`