ZEND_AST_REF     1241 Zend/zend_ast.c 		case ZEND_AST_REF:
ZEND_AST_REF     3891 Zend/zend_compile.c 	zend_bool by_ref = value_ast->kind == ZEND_AST_REF;
ZEND_AST_REF     3900 Zend/zend_compile.c 		if (key_ast->kind == ZEND_AST_REF) {
ZEND_AST_REF      540 Zend/zend_language_parser.y 	|	'&' variable		{ $$ = zend_ast_create(ZEND_AST_REF, $2); }