How to remove trailing whitespace on save

I am using MATLAB R2018b. Does matlab provide function to remove trailing white spaces on saving file ?

[madhan ravi]

uplod your code

[Jan]

Remove white space from what? From strings, filenames, images?

[Hafiz Luqman]

@jan , from code, editor file.

From photo too, but its optional. Git gives me changes in file if white spaces left at the end of line.

[Jan]

@Hafiz: Sorry, you want a tool which removes white spaces from source code and photos? How strange.

[Hafiz Luqman]

@jan the word 'optional' mean nice to have. Main query is about remove whitespaces from code. Only those people who know answer/solution are welcomed to comment or reply. Thanks

Answer 1

[Jan]

No, there is no such builtin tool. You can use a simple tool like this to cleanup your code:

!!!!!!! TEST THIS EXHAUSTUIVELY BEFORE USING !!!!!!!!!!

function CleanMyFile(FileName)
S = fileread(FileName);
C = strsplit(S, '\n');
C = deblank(C);
C = strrep(sprintf('\t'), blank(3));  % Replace TAB by 3 spaces
fid = fopen(FileName, 'w');
if fid == -1
    error('Cannot open file for writing: %s', FileName);
end
fprintf(fid, '%s\n', C{:});
fclose(fid);
end

I added a conversion of TABs to spaces. Maybe you want to call it for all your files:

Base  = 'C:\YourMatlabFolder';
Files = dir(fullfile(Base, '\**\*.m'));
for k = 1:numel(Files)
    FileName = fullfile(Files(k).folder, Files(k).name);
    fprintf('Cleaning: %s\n', FileName);
    CleanMyFile(FileName);
end

You could do the same with all open files in the editor:

function CleanupEditorFiles(Opt)
if nargin == 0
    Opt = 'active';        % Or 'all' if you like
end
if strcmpi(Opt, 'active')  % Active file:
    AllDoc = matlab.desktop.editor.getActive;
else                       % All open files:
    AllDoc = matlab.desktop.editor.getAll;
end

for iDoc = 1:numel(AllDoc)
   Doc  = AllDoc(iDoc);
   File = Doc.Filename;
   Name = GetFileName(File);
   
   % No actions if file is opened as read-nonly:
   if ~Doc.Editable
      fprintf('  Locked: %s\n', Name);
      continue;
   end
   
   origText = Doc.Text;
   C = strsplit(origText, '\n');
   C = deblank(C);
   C = strrep(sprintf('\t'), blank(3));  % Replace TAB by 3 spaces
   newText = sprintf(fid, '%s\n', C{:});
   
   if ~strcmp(newText, origText)
      fprintf('  update: %s\n', File);
      cursor   = Doc.Selection;
      Doc.Text = newText;
      
      % Restore cursor position, but not the selection:
      if ~isempty(cursor)
         Doc.goToPositionInLine(cursor(1), 1);
      end
   end
end

!!!!!!! TEST THIS EXHAUSTUIVELY BEFORE USING !!!!!!!!!!

Create a backup before testing. This was written in the editor of the forum. Add meaningful comments, if you like the function.

Answer 2

[Tim]

See answer on SO: https://stackoverflow.com/a/21171788/2909078