method

freeze

v1_8_7_72 - Show latest stable - 0 notes - Class: Object

freeze() public

Prevents further modifications to obj. A TypeError will be raised if modification is attempted. There is no way to unfreeze a frozen object. See also Object#frozen?.

   a = [ "a", "b", "c" ]
   a.freeze
   a << "z"

produces:

   prog.rb:3:in `<<': can't modify frozen array (TypeError)
    from prog.rb:3

Show source

/*
 *  call-seq:
 *     obj.freeze    => obj
 *  
 *  Prevents further modifications to <i>obj</i>. A
 *  <code>TypeError</code> will be raised if modification is attempted.
 *  There is no way to unfreeze a frozen object. See also
 *  <code>Object#frozen?</code>.
 *     
 *     a = [ "a", "b", "c" ]
 *     a.freeze
 *     a << "z"
 *     
 *  <em>produces:</em>
 *     
 *     prog.rb:3:in `<<': can't modify frozen array (TypeError)
 *      from prog.rb:3
 */

VALUE
rb_obj_freeze(obj)
    VALUE obj;
{
    if (!OBJ_FROZEN(obj)) {
        if (rb_safe_level() >= 4 && !OBJ_TAINTED(obj)) {
            rb_raise(rb_eSecurityError, "Insecure: can't freeze object");
        }
        OBJ_FREEZE(obj);
    }
    return obj;
}

freeze

Related methods