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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: OO, C++, and something much better!
Date: 1997/01/27
Message-ID: <dewar.854377239@merv>#1/1
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references: <JSA.97Jan16141937@alexandria> 	<5buodl$bci@boursy.news.erols.com>
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organization: New York University
newsgroups: 
 comp.object,comp.lang.c++,comp.lang.ada,comp.lang.smalltalk,comp.lang.eiffel
Date: 1997-01-27T00:00:00+00:00
List-Id: <comp.lang.ada>


Richard said

" - dynamic checking has a run time cost; other things being equal it
   is better to move it to compile time


The advantage in moving checking to compile time is much more than an
efficiency concern. The checks made at at compile time establish absolute
invariants, such that the corresponding errors cannot possibly occur in any
possible execution of the program.

Runtime checks tell you only that a specific execution of the program did
not fail the checks, and are thus subject to the fundamental weakness of
all dynamic based testing methods -- they can establish the presence of bugs,
but they cannot easily be used to prove the absence of bugs.