INI2STRUCT Parses .ini file

Returns a structure with section names and keys as fields.

Based on init2struct.m by Andriy Nych

function Struct = ini2struct(filename)
arguments
  filename (1,1) string {mustBeFile}
end

f = fopen(filename,'r');                    % open file

while ~feof(f)                              % and read until it ends
  s = strtrim(fgetl(f));                  % remove leading/trailing spaces
  if is_comment(s) % skip empty & comments lines
    continue
  end
  if s(1)=='['                            % section header
    Section = matlab.lang.makeValidName(strtok(s(2:end), ']'));
    Struct.(Section) = [];              % create field
    continue
  end

  [Key,Val] = strtok(s, '=');             % Key = Value ; comment
  Val = strtrim(Val(2:end));              % remove spaces after =

  if is_comment(Val) % empty entry
    Val = [];
  elseif Val(1)=='"'                      % double-quoted string
    Val = strtok(Val, '"');
  elseif Val(1)==''''                     % single-quoted string
    Val = strtok(Val, '''');
  else
    Val = strtok(Val, ";");             % remove inline comment
    Val = strtok(Val, "#");             % remove inline comment
    Val = strtrim(Val);                 % remove spaces before comment

    Val = double(string(Val));
    % convert string to number(s)
  end

  if ~exist('Section', 'var')             % No section found before
    Struct.(matlab.lang.makeValidName(Key)) = Val;
  else                                    % Section found before, fill it
    Struct.(Section).(matlab.lang.makeValidName(Key)) = Val;
  end

end

fclose(f);

end % function


function i = is_comment(line)
% a comment line detected

i = isempty(line) || any(startsWith(line, [";", "#"]));

end

% Copyright (c) 2014, freeb
% Copyright (c) 2008, Andriy Nych
% Copyright (c) 2009-2010, Evgeny Prilepin aka Iroln
% All rights reserved.

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