[m-dev.] for review: add MC++ implementation of library and runtime

Fergus Henderson fjh at cs.mu.OZ.AU
Tue Dec 5 23:08:54 AEDT 2000


On 05-Dec-2000, Tyson Dowd <trd at cs.mu.OZ.AU> wrote:
> Lots of review comments have been of the form:
> 
> "What happens when ...."
> "Why don't you ... "
> "Surely there's a class method for ..."
> "Can't you just ..."
> 
> The answer to all of these is "I don't know" or "This seemed to work
> at the time".
> 
> I've asked exactly the same questions while I was writing the code.
> 
> On average to answer questions like this it has taken 1 hour per
> question.  This is because the documentation is often non-existant or so
> vacuous that it is useless, the class libraries are written to ad-hoc
> specifications (e.g. no attempt at POSIX compatibility or other useful,
> "complete" standards) and the runtime system itself gives poor error
> messages.

OK, in that case we may find that it takes a long time to fully
implement the IL version of the library.

This diff need not implement the complete library.  What we need to do
with the prototype is just to make sure that for all the places where
we are not sure what to do, we (a) mark them with an XXX so that we
know to go back and revisit them and (b) make sure that things will
fail cleanly (e.g. calling SORRY()) rather than working most of the
time and then failing nastily in rare cases.

Note that debugging the cases where something works most of the time
but occaisionally fails will typically cost a lot more than one hour
per bug.

-- 
Fergus Henderson <fjh at cs.mu.oz.au>  |  "I have always known that the pursuit
                                    |  of excellence is a lethal habit"
WWW: <http://www.cs.mu.oz.au/~fjh>  |     -- the last words of T. S. Garp.
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