PHP Internals Deep Dive

Zend/zend_object_handlers.c



@@ -1251,6 +1258,8 @@ ZEND_API void zend_std_unset_dimension(zend_object *object, zval *offset) /* {{{
                zend_call_known_instance_method_with_1_params(funcs->zf_offsetunset, object, NULL, &tmp_offset);
                OBJ_RELEASE(object);
                zval_ptr_dtor(&tmp_offset);
+       } else if (zend_class_implements_interface(ce, zend_ce_collection)) {
+               zend_collection_unset_item(object, offset);
        } else {
                zend_bad_array_access(ce);
        }

Zend/zend_collection.c



void zend_collection_unset_item(zend_object *object, zval *offset)
{
       zval rv;
       zval *value_prop;
       zend_class_entry *ce = object->ce;

       if (!key_type_allowed(ce, offset)) {
               return;
       }

       value_prop = zend_read_property_ex(ce, object, ZSTR_KNOWN(ZEND_STR_VALUE), true, &rv);

       if (Z_TYPE_P(offset) == IS_STRING) {
               zend_hash_del(HASH_OF(value_prop), Z_STR_P(offset));
       } else {
               zend_hash_index_del(HASH_OF(value_prop), Z_LVAL_P(offset));
       }
}