Re: Uninitialized "out" parameters

[ok@goanna.cs.rmit.edu.au (Richard A. O'Keefe)]

frank@bigdog.engr.arizona.edu (Frank Manning) writes:

:In article <4t4r0s$8te@goanna.cs.rmit.edu.au> ok@goanna.cs.rmit.edu.au
:(Richard A. O'Keefe) writes:

:>          Roughly the third most frightening thing I have seen in a computer
:> manual is the advice
:>         "If your program is halting with range-checking errors,
:>          and you don't want to address those problems immediately,
:>          you can always omit the {$R+} compiler directive
:>          [thus suppressing the range checks] for the time being."
:> to be found in the Turbo Pascal 5.0 User Guide on p207.

:Not to be argumentative, but I'm curious as to why you think this is so
:bad?

Because once such a check would have failed, the program is operating
in never-never land, and any *other* problems you may chose to address
first may, in fact, be artefacts of the nonsense you are guaranteed to
be getting.

If your program is halting with range-checking errors,
the only kind of problem that it is useful to diagnose is a problem
that occurs *before* that halt.  Which means that you want to switch
additional checks on so the program halts *earlier*, if anything.

This is especially true in a programming language running on old DOS,
where a range check failure that is not caught may mean that your
program has just scribbled all over the operating system or the debugger...
-- 
Fifty years of programming language research, and we end up with C++ ???
Richard A. O'Keefe; http://www.cs.rmit.edu.au/~ok; RMIT Comp.Sci.