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From: pw@tnoibbc.UUCP (Peter Willems)
Newsgroups: comp.lang.eiffel
Subject: repeating assertions ?
Keywords: assertions
Message-ID: <2190@tnoibbc.UUCP>
Date: 30 Nov 90 15:00:10 GMT
Lines: 41

Consider the next example consisting of two classes A and B.
B inherits from A and uses A's Create feature:

class A
feature
	identifier: STRING;

	Create (s: STRING) is
		require
			s_exists: not s.Void
		do
			identifier := s
		ensure
			identifier = s
		end; -- Create
end -- class A

class B
inherit
	A
		rename Create as a_Create
feature
	Create (s: STRING) is
		do
			a_Create (s)
		end; -- Create
end -- class B

Question: should class B repeat the assertions specified with the
Create feature in class A ?
If not than essential class interface information will be omitted
in the documentation provided by flat and short.
However, repeating this information seems contradictory with the
object-oriented rule of reusability.

Any suggestions ?
-- 
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