Word wrap in Python's curses library

    class WindowFullException(Exception):
        pass

    def addstr_wordwrap(window, s, width, height, mode=0):
        """ (cursesWindow, str, int, int) -> None

        Add a string to a curses window with given dimensions. If mode is given 
        (e.g. curses.A_BOLD), then format text accordingly. We do very 
        rudimentary wrapping on word boundaries.

        Raise WindowFullException if we run out of room.
        """
        # TODO Is there really no way to get the dimensions of a window programmatically?
        # passing in height and width feels ugly.

        (y, x) = window.getyx() # Coords of cursor
        # If the whole string fits on the current line, just add it all at once
        if len(s) + x <= width:
            window.addstr(s, mode)
        # Otherwise, split on word boundaries and write each token individually
        else:
            for word in words_and_spaces(s):
                if len(word) + x <= width:
                    window.addstr(word, mode)
                else:
                    if y == height-1:
                        # Can't go down another line
                        raise WindowFullException()
                    window.addstr(y+1, 0, word, mode)
                (y, x) = window.getyx()

    def words_and_spaces(s):
        """
        >>> words_and_spaces('spam eggs ham')
        ['spam', ' ', 'eggs', ' ', 'ham']
        """
        # Inspired by http://stackoverflow.com/a/8769863/262271
        return list(itertools.chain.from_iterable(zip(s.split(), itertools.repeat(' '))))[:-1] # Drop the last space