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From: heyman@acad.stedwards.edu (Jerry Heyman)
Subject: Re: Static vs Dynamic Typing: Effects on Productivity?
Message-ID: <1994Sep1.162002.24832@acad.stedwards.edu>
Date: Thu, 1 Sep 1994 16:20:02 GMT
References: <DERWAY.94Aug23180251@alumni.ndc.com> <1994Aug25.172702.4984@rcmcon.com> <mikec.21.000B26F7@metronet.com> <CvEFLs.3vz@bony1.bony.com> <CvEow0.54r@bony1.bony.com>
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Richard Bielak (richieb@bony1.bony.com) wrote:
> In article <CvEFLs.3vz@bony1.bony.com> richieb@bony1.bony.com (Richard Bielak) writes:

> >
> >Recall this sentiment of an old programmer:
> >
> >    "Testing only proves the existence of errors, not their absense."
>                                                              ^^^^^^^
> >
> >On the other hand, a type checker proves the _absense_ of type errors.

Well, I guess this is true - but what if the programmer casts a variable?
The type might be correct (because they cast it to the type they need), but
is the data valid?

> ...richie
> -- 
> * Richie Bielak   (212)-635-4835   | 

jerry
-- 
Jerry Heyman                by day  : IBM AIX Development, RISC System/6000 Div
                            Internet: jerry@austin.ibm.com
heyman@acad.stedwards.edu   by nite : Adjunct Lecturer, St. Edward's Univ.
*All comments are my own and should not be construed to represent any one else
