function cdirs = catdirs(caller, varargin)

%CATDIRS Concatenate separate strings of directories into one string. 

%   CATDIRS  CALLER DIRNAME checks that DIRNAME is a string, removes any

%   leading or tailing whitespace, and appends a path separator. CALLER is

%   the name of the calling function, used only when displaying warnings.

%

%   CATDIRS  CALLER DIR1 DIR2 DIR3 ... for each input, checks it is a

%    string, removes any leading or tailing whitespace, and appends a path

%    separator; and then concatenates all these strings. CALLER is the

%    name of the calling function, used only when displaying warnings.

%

%   Example:

%       dirlist = catdirs('addpath', '/home/user/matlab','/home/user/matlab/test');

%   Copyright 1984-2015 The MathWorks, Inc.

n= nargin-1; 

narginchk(2,Inf); 

cdirs = ''; 

for i=1:n 

    next = varargin{i}; 

    if ~ischar(next) 

        error(message('MATLAB:catdirs:ArgNotString'));

    end

    % Remove leading and trailing whitespace

	trimmedNext = strtrim(next); 

    if ~isempty(trimmedNext) 

        if ~strcmp(trimmedNext, next) 

            [~,caller]=fileparts(caller);

            switch caller

                case 'addpath'

                    warning(message('MATLAB:catdirs:AddLeadingTrailingWhitespace', ...

                        trimmedNext, next));

                case 'rmpath'

                    warning(message('MATLAB:catdirs:RemoveLeadingTrailingWhitespace', ...

                        trimmedNext, next));

            end

        end

        cdirs = [cdirs trimmedNext pathsep]; %#ok<AGROW> 

    end 

end