Display visited file's path in the frame title

I’m fond of seeing somewhere the full path to the file I’m currently editing(as opposed to just the file name displayed in modeline). Emacs’s frame title seems like a good place to display such information, since by default it doesn’t show anything interesting. Here’s how we can achieve this:

(setq frame-title-format
      '((:eval (if (buffer-file-name)
                   (abbreviate-file-name (buffer-file-name))

The path will be displayed in an abbreviated manner(/home/bozhidar/ will be shortened to just ~/). If you’d like to see the expanded path just remove the abbreviate-file-name function invocation. If a buffer is not visiting a file, the buffer’s name would be displayed instead.

Prelude sets frame-title-format like this by default.