Philosophy of Yedit


yedit and zedit are code editors, not text editors

yedit and zedit are not full of windows, decoration or other gadgets, with an opaque screen full of overlapping window. It is now the software fashion, not necessary a good thing. The most important is your code and the possibility to destroy it, not the colors or gadgets of your editor.

yedit and zedit are specially developed for scientific users. For them the most important is the code, not the decoration. Many editors have a lot of windows and a user will loose hours to learn how to use them. Special mode of working has been made in yedit and zedit to protect the code:

  • Open the file in a read only mode, you can extract lines of code but not modify the code. No possibility of edit in the wrong editor.
  • You can open, as many yedit or zedit you want, on the same file, to see different parts of a big code. After you make a save on any yedit or zedit , the others are immediately updated. If you do not have this, you have a big chance to destruct your code, by editing alternatively on the different editors, now you can make that.

FORTRAN77 in the fixed format of 72 columns and Fortran90, 95 and 2003, have also a special format of 132 columns. The usual editors do not know these particularities of the Fortran language. So special editors must be used not to go after the max 72 or 132. Another thing, is to go with a Fn key, to the 7th column.

All the other editors are derived from text editors like Words of Microsoft, which considers the text as an unstructured file of words. Fortran is basicaly a file with lines of code, not words. A line is a line, like other editors, but with its continuation lines also. In Fortran, a line with its 32 continuation lines (for example) is a line, not 33 lines.

In the other editors, if you move the cursor along the page, you cannot go after the last non blank character of a line. In yedit or zedit you can go immediately anywhere in a line. It is the work of yedit and zedit to fill the lines of code with blank when you edit a file and to suppress them, and introduce automatically tabs, when you save.

A special functionality, perhaps unique within other editors, is the fact that with the F3 and F4 key, you can cut a line in two, or concatenate two lines, but within the syntax of Fortran. Make the experience with yedit (fixed format) and zedit (free format), observe the difference with the continuation lines. Concatenate is between lines of code or lines of comment but not mixed.

It is these sophisticated details which make a good editor for development and not a Word editor of unstructured words.

Move the cursor or scroll vertically the edited code with the cursor at the top or the bottom, and see the difference. You have lines full of 72 characters (yedit) or 132 characters (zedit). It is the task of yedit or zedit to eliminate the blanks, and to introduce automatically the tab when you save, and to replace the tab with blank and to complete the line of blanks to obtain 72 or 132 characters when you read the code. You can move the cursor at any place and not between the first and last not blank character of the line. A very unacceptable method of working of the majority of editors which are derived from text editor and not code editor.

The working mode of editing is different from the other editors : The place where you type an edit command is not the same : its depend on the range of the modification you hope :

  • If you make modification in a single line, you can type directly, but by default in replacement mode, not insert mode, you can put on insert mode by the insert key but after type on the Insert key, and again to obtain the replacement mode.
  • If you make modifications on full lines you pass with the tab key in the prefix zone where you can read the number of the lines and you type your commands.
  • If you make modifications on the whole file you pass in the top command line with the Enter key and you type the command. The Enter key is the right Enter key.


With that logic you minimize the risk of destroy your code.

You can use the mouse with two buttons:

  • The left button : you can put the cursor anywhere on the text of the file you are editing.
  • The right button without Shift : you create a window with a limited number of direct command. If you edit a file by the command of opening a file inside yedit or zedit, it is opened in a read only mode (The good method to use to extract lines of code or examine but not modify your code).
  • The right button with Shift : you can modify directly the coloring syntax.

When you edit, you have behind you a "witch which" observe your editing work. If you make anything, which is really bad within Fortran context, you see a flashing window and you ear a bell ringing.

The first time you are working with yedit or zedit you automatically stumbled on two problems :

  • Do not clic on yedit.exe or zedit.exe, the exec file of yedit or zedit. To edit a file you can use one of these methods:
    • Open a DOS window and type for example :yedit essai.f
    • Open the Windows control panel to automatically open the file of type *.f with yedit and the files of type *.f90 or *.f95 with zedit . After that, you can click on any file of those types and they are opened with yedit or zedit.
    • Open a file inside yedit and zedit , and it is opened in the read only mode ( the method you must used to protect your code)

  • The left Enter key and right Enter key do not make the same job, on the other editors they make the same job :
    • The Return key = the left Enter key, goes to the following line of code.
    • The Enter key = the right Enter key, executes commands which are on the prefixed columns or in the command line.