if <assignment>:

[Delaney, Timothy]

> From: maney at pobox.com [mailto:maney at pobox.com]
> 
> David Brown <david at no.westcontrol.spam.com> wrote:
> > correctness.  This particular "feature" is a huge source of bugs and
> > frustration in C programming - mixing up "=" and "==" in 
> conditions is
> > probably the biggest single cause of C program bugs.  
> Python, on the other
> 
> Are you speaking from experience, or is this as well-founded as the
> hysterical wails about how Python's use of indentation is just wrong? 
> It certainly isn't remotely near my own experience (which covers a bit
> more than two decades, during much of which C was used more than
> anything else).

Actually, there have been extensive studies (none of which I can quote right
now ;) which have determined that the most common causes of errors in C/C++
programs are simple typos which are allowed by the syntax, but change the
semantics of the program. Of course we're talking about *coding* errors here
- nothing else (such as poor design, relying on the behaviour of an
"implementation defined" feature, etc).

The most common of these are = vs ==, and just about anything to do with
pointer dereferencing.

The next most common class of errors involve memory issues - dereferencing
invalid pointers, double-freeing, failing to free memory, etc.

ObRant: What the hell is the difference between an "implementation defined"
feature, and an "undefined" feature? In both cases, a particular
implementation is free to do whatever it wants. The only possible difference
I can think of is that "implementation defined" implies that the
implementation should at least try to do something useful ... and actually
document what it does.

Tim Delaney