Regular expression to apply backspace characters

Question

I have a string coming from a telnet client. This string contains backspace characters which I need to apply. Each backspace should remove one previously typed character.

Answer 1

I wouldn't try to use a regular expression for this, since it's very impenetrable to read and I have the feeling that it's not even possible with plain regular expression without any perl-like regex magic-extensions. My suggestion would be something like (python like pseudocode):

stack = []
for char in str:
    if char == BACKSPACE and not stack.isEmpty():
        stack.pop()
    else:
        stack.push(char)

result = ''.join(stack)

It'S immediately clear what happens and how it works.