/Lib/curses/wrapper.py

 1"""curses.wrapper
 2
 3Contains one function, wrapper(), which runs another function which
 4should be the rest of your curses-based application.  If the
 5application raises an exception, wrapper() will restore the terminal
 6to a sane state so you can read the resulting traceback.
 7
 8"""
 9
10import curses
11
12def wrapper(func, *args, **kwds):
13    """Wrapper function that initializes curses and calls another function,
14    restoring normal keyboard/screen behavior on error.
15    The callable object 'func' is then passed the main window 'stdscr'
16    as its first argument, followed by any other arguments passed to
17    wrapper().
18    """
19
20    res = None
21    try:
22        # Initialize curses
23        stdscr=curses.initscr()
24
25        # Turn off echoing of keys, and enter cbreak mode,
26        # where no buffering is performed on keyboard input
27        curses.noecho()
28        curses.cbreak()
29
30        # In keypad mode, escape sequences for special keys
31        # (like the cursor keys) will be interpreted and
32        # a special value like curses.KEY_LEFT will be returned
33        stdscr.keypad(1)
34
35        # Start color, too.  Harmless if the terminal doesn't have
36        # color; user can test with has_color() later on.  The try/catch
37        # works around a minor bit of over-conscientiousness in the curses
38        # module -- the error return from C start_color() is ignorable.
39        try:
40            curses.start_color()
41        except:
42            pass
43
44        return func(stdscr, *args, **kwds)
45    finally:
46        # Set everything back to normal
47        stdscr.keypad(0)
48        curses.echo()
49        curses.nocbreak()
50        curses.endwin()