function f = fullfile(varargin)

%FULLFILE Build full file name from parts.

%   F = fullfile(FOLDERNAME1, FOLDERNAME2, ..., FILENAME) builds a full

%   file specification F from the folders and file name specified. Input

%   arguments FOLDERNAME1, FOLDERNAME2, etc. and FILENAME can be strings,

%   character vectors, or cell arrays of character vectors. Non-scalar

%   strings and cell arrays of character vectors must all be the same size.

%

%   If any input is a string array, F is a string array. Otherwise, if any

%   input is a cell array, F is a cell array.  Otherwise, F is a character

%   array.

%

%   The output of FULLFILE is conceptually equivalent to character vector

%   horzcat operation:

%

%      F = [FOLDERNAME1 filesep FOLDERNAME2 filesep ... filesep FILENAME]

%

%   except that care is taken to handle the cases when the folders begin or

%   end with a file separator.

%

%   FULLFILE collapses inner repeated file separators unless they appear at 

%   the beginning of the full file specification. FULLFILE also collapses 

%   relative folders indicated by the dot symbol, unless they appear at 

%   the end of the full file specification. Relative folders indicated 

%   by the double-dot symbol are not collapsed.

%

%   To split a full file name into folder parts, use split(f, filesep).

%

%   Examples

%     % To build platform dependent paths to files:

%        fullfile(matlabroot,'toolbox','matlab','general','Contents.m')

%

%     % To build platform dependent paths to a folder:

%        fullfile(matlabroot,'toolbox','matlab',filesep)

%

%     % To build a collection of platform dependent paths to files:

%        fullfile(toolboxdir('matlab'),'iofun',{'filesep.m';'fullfile.m'})

%

%   See also FILESEP, PATHSEP, FILEPARTS, GENPATH, PATH, SPLIT.

%   Copyright 1984-2018 The MathWorks, Inc.

    narginchk(1, Inf); 

    persistent fileSeparator; 

    if isempty(fileSeparator) 

        fileSeparator = filesep;

    end 

    theInputs = varargin; 

    containsCellOrStringInput = false; 

    containsStringInput = false;  

    for i = 1:nargin 

        inputElement = theInputs{i}; 

        containsCellOrStringInput = containsCellOrStringInput || iscell(inputElement); 

        if isstring(inputElement) 

            containsStringInput = true; 

            containsCellOrStringInput = true; 

            theInputs{i} = convertStringsToChars(theInputs{i});

        end 

        if ~ischar(theInputs{i}) && ~iscell(theInputs{i}) && ~isnumeric(theInputs{i}) && ~isreal(theInputs{i}) 

            error(message('MATLAB:fullfile:InvalidInputType'));

        end 

    end 

    f = theInputs{1}; 

    try 

        if nargin == 1 

            if ~isnumeric(f)

                f = refinePath(f, fileSeparator);

            else 

                f = char(f); 

            end

        else 

            if containsCellOrStringInput 

                theInputs(cellfun(@(x)~iscell(x)&&isempty(x), theInputs)) = [];

            else 

                theInputs(cellfun('isempty', theInputs)) = ''; 

            end 

            if length(theInputs)>1 

                theInputs{1} = ensureTrailingFilesep(theInputs{1}, fileSeparator); 

            end 

            if ~isempty(theInputs) 

                theInputs(2,:) = {fileSeparator}; 

                theInputs{2,1} = ''; 

                theInputs(end) = ''; 

                if containsCellOrStringInput 

                    f = strcat(theInputs{:});

                else 

                    f = [theInputs{:}]; 

                end 

            end 

            f = refinePath(f,fileSeparator); 

        end 

    catch

        locHandleError(theInputs(1,:));

    end 

    if containsStringInput 

        f = string(f);

    end 

end