WP_Object_Cache::is_valid_key( int|string $key ): bool

140	protected function is_valid_key( $key ) {141		if ( is_int( $key ) ) {142			return true;143		}144 145		if ( is_string( $key ) && trim( $key ) !== '' ) {146			return true;147		}148 149		$type = gettype( $key );150 151		if ( ! function_exists( '__' ) ) {152			wp_load_translations_early();153		}154 155		$message = is_string( $key )156			? __( 'Cache key must not be an empty string.' )157			/* translators: %s: The type of the given cache key. */158			: sprintf( __( 'Cache key must be an integer or a non-empty string, %s given.' ), $type );159 160		_doing_it_wrong(161			sprintf( '%s::%s', __CLASS__, debug_backtrace( DEBUG_BACKTRACE_IGNORE_ARGS, 2 )[1]['function'] ),162			$message,163			'6.1.0'164		);165 166		return false;167	}