Re: Bug-free software (was: Re rant about viruses on VMS...)

[der Mouse <mouse () Rodents Montreal QC CA>]

> By "bug free software" I mean software that behaves entirely in
> accordance with the original defined requirements.  Getting the
> requirements right is another matter altogether.

If by this you mean that software mechanically derived from a
human-produced hundred-thousand-line formal specification is bug-free
because it is an accurate implementation of the specification, I submit
that that is a redefinition of "bug-free" that is so misleading that it
isn't unfair to call it outright wrong.

Bugs and their generation must, to be meaningful, be measured at the
point at which humans produce stuff which is then mechanically
processed into something the machine can execute.  Whether you call the
language in which this human/computer interfacing takes place a
programming language or a formal specification language is a
terminology distinction of no real import.

Now of course you might be talking about higher-level requirements
documents, in which case you have something of a point - but when a
malfunction occurs, whether the bug is in the code written to implement
the requirements document or in the requirements document itself is a
distinction of little import to the end-user with the problem; all it
affects is whom to blame, and that much only at levels at which there
is a distinction between the sources of the two.

/~\ The ASCII                           der Mouse
\ / Ribbon Campaign
 X  Against HTML               [EMAIL PROTECTED]
/ \ Email!           7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B