text: 
  export function has_prop(target, prop) { return prop in Object(target); }
  export function get_prop(target, prop) { return target[prop]; }
  export function set_prop(target, prop, value) { target[prop] = value; }
  export function type_of(a) { return typeof a; }
  export function instance_of(lhs, rhs) { return lhs instanceof rhs; }
  