code: func (om *OrdMap) Put(key, val interface{}) {
  	rkey := ty.AssertType(key, om.ktype)
  	rval := ty.AssertType(val, om.vtype)
  	if !om.exists(rkey) {
  		om.keys = reflect.Append(om.keys, rkey)
  	}
  	om.m.SetMapIndex(rkey, rval)
  }
docs: // Put has a parametric type:
  //
  //	func (om *OrdMap<K, V>) Put(key K, val V)
  //
  // Put adds or overwrites `key` into the map `om` with value `val`.
  // If `key` already exists in the map, then its position in the ordering
  // of the map is not changed.