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Date: Tue, 13 May 2014 14:46:39 +0200
From: "G.B." <rm-dash-bau-haus@dash.futureapps.de>
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Subject: Re: Weird error with Dynamic_Predicate
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Date: 2014-05-13T14:46:38+02:00
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On 12.05.14 21:47, mockturtle wrote:
> Any ideas?

 From a different angle, a rule of contract-based design---
assuming the lessons learned from DbC---is not a substitute
for input checking. While I guess you have your reasons for
attaching the Dynamic_Predicate to a string type, if you
are preforming proofs, which DbC would oblige you to do,
there is a different strategy:

By the above rule (about DbC not being input checking),
some I/O routine would check the syntax;
then, if the characters form a well formed string, the object
can be converted to a different string type; this string
type does not have the dynamic check attached, since after
the checking routine is done, the type's objects are known
to have only good values.