1. If a tab is entered at the prompt, allow it to be backspaced away.
2. Eliminate the beep when hitting <enter> at the prompt.
want = ((have - 1) // self.indentwidth) * self.indentwidth
ncharsdeleted = 0
while 1:
+ if chars == sys.ps1:
+ break
chars = chars[:-1]
ncharsdeleted = ncharsdeleted + 1
have = len(chars.expandtabs(tabwidth))
text.mark_set("insert", first)
line = text.get("insert linestart", "insert")
i, n = 0, len(line)
+ if line == sys.ps1:
+ return "break"
while i < n and line[i] in " \t":
i = i+1
if i == n: