You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: smoothfun.m
    path of file: ./repos/chebfun/@smoothfun
    
    the code of the file until where you have to start completion: classdef smoothfun < onefun % (Abstract) 
%SMOOTHFUN   Approximate smooth functions on [-1,1]. 
%   Abstract (interface) class for approximating smooth functions on the
%   interval [-1,1].
%
% Constructor 
    
function out = isPeriodicTech(f)
        %ISPERIODICTECH   Test if a SMOOTHFUN is constructed with a
        %basis of periodic functions. 
        %   Individual techs override this function as necessary.
            
            % Returns 0 by default.
            out = 0;
            
        end