Re: [tlug] GPL and Linux in Dvico Tivx

["Stephen J. Turnbull" <stephen@example.com>]

>>>>> "Josh" == Josh Glover <jmglov@example.com> writes:

    Josh> The process for avoiding bugs is actually quite similar to
    Josh> the process for finding and fixing them (credit goes to Ota
    Josh> for summing this up succinctly): identify your assumptions
    Josh> and isolate them, then verify that all of these assumptions
    Josh> hold, both independently and in concert.  Think about what
    Josh> might happen if they do not hold.

Not really similar, though.  To find a bug in a concrete program,
there's a practical specification for correctness: "mostly behaves the
same as this program, but does not exhibit undesirable behavior X".
This requires only understanding the source code syntax and
the semantics in concrete terms.

To avoid the bug, you need a much more detailed model of the world,
which not only understands the concrete semantics, but also possesses
a map from concrete semantics to the world where the customer's
specifications live (Xanadu? ;-)

This is why "code and fix" development and its systematized successor
(the Cascade of Attention-Deficit Teenagers) are so popular.  ;-)

-- 
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              ask what your business can "do for" free software.