Indentation

Indentation is a coding style that emphasizes the logical structure of blocks. It is the easiest way to prevent bugs. More details can be found in the exercise book.

• Not necessary for the computer
• Absolutely necessary for the programmer / maintainer
• After each opening brace {: new line and tab (2 characters)
• Each closing brace } is on a new line and ``untabbed''
  

  double x, y, z, epsilon;
  ...
  if (fabs(x) < epsilon) {
  if (fabs(y) < epsilon) {
  if (fabs(z) < epsilon) {
  for(int i = 0; i < n; i++) {
  x *= y*z;
  }
  }
  }
  }

Proper indentation can be obtained by editing source files with the GNU Emacs text editor.

• Traditional GNU/Linux text editor: emacs emacs programName.cxx
• Many key-combination commands (try ignoring menus!)
• Legenda: C-key: CTRL+key, M- key: ALT+key (for keyboards with no ALT key or for remote connections can obtain same effect by pressing and releasing ESC and then key)
• Basics:
  1. C-x C-s: save file in current buffer (screen) with current name (will ask for one if none is supplied)
  2. C-x C-c: exit (will ask for confirmation for unsaved files)
  3. C-space: start selecting text (selection ends at cursor position)
  4. C-w: cut, M-w: copy, C-y: paste
  5. tab: indents C/C++ code
  6. M-x indent-region: properly indents all selected region