Method: Object#remove_instance_variable

Defined in:
variable.c

#remove_instance_variable(symbol) ⇒ Object #remove_instance_variable(string) ⇒ Object

Removes the named instance variable from obj, returning that variable’s value. String arguments are converted to symbols.

class Dummy
  attr_reader :var
  def initialize
    @var = 99
  end
  def remove
    remove_instance_variable(:@var)
  end
end
d = Dummy.new
d.var      #=> 99
d.remove   #=> 99
d.var      #=> nil

Overloads:

  • #remove_instance_variable(symbol) ⇒ Object

    Returns:

  • #remove_instance_variable(string) ⇒ Object

    Returns:



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# File 'variable.c', line 1633

VALUE
rb_obj_remove_instance_variable(VALUE obj, VALUE name)
{
    VALUE val = Qnil;
    const ID id = id_for_var(obj, name, an, instance);
    st_data_t n, v;
    struct st_table *iv_index_tbl;
    st_data_t index;

    rb_check_frozen(obj);
    if (!id) {
	goto not_defined;
    }

    switch (BUILTIN_TYPE(obj)) {
      case T_OBJECT:
        iv_index_tbl = ROBJECT_IV_INDEX_TBL(obj);
        if (!iv_index_tbl) break;
        if (!st_lookup(iv_index_tbl, (st_data_t)id, &index)) break;
        if (ROBJECT_NUMIV(obj) <= index) break;
        val = ROBJECT_IVPTR(obj)[index];
        if (val != Qundef) {
            ROBJECT_IVPTR(obj)[index] = Qundef;
            return val;
        }
	break;
      case T_CLASS:
      case T_MODULE:
	n = id;
	if (RCLASS_IV_TBL(obj) && st_delete(RCLASS_IV_TBL(obj), &n, &v)) {
	    return (VALUE)v;
	}
	break;
      default:
	if (FL_TEST(obj, FL_EXIVAR)) {
	    if (generic_ivar_remove(obj, id, &val)) {
		return val;
	    }
	}
	break;
    }

  not_defined:
    rb_name_err_raise("instance variable %1$s not defined",
		      obj, name);
    UNREACHABLE_RETURN(Qnil);
}