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| {{Warning|'''Warning''': Article under development}} | | {{Warning|'''Warning''': Article under development}} |
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| ==Introduction== | | ====Introduction==== |
| This article discusses issues recently discovered for the following two validity rules:
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| 8.15.7 Validity: ''Conversion Procedure rule'', Validity code: '''VYCP'''<br>
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| 8.15.8 Validity: ''Conversion Query rule'', Validity code: '''VYCQ'''
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| ==Examples==
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| For the following examples eweasel tests have been created. Their named
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| ====Example 1====
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| eweasel test: convert-to-current-type
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| <code>[eiffel,N]
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| class A[G]
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| convert
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| to_a: {A[G]}
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| feature
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| to_a: A[G]
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| end
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| </code>
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| The conversion to '''A[G]''' should indeed not be valid because they are conform.
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| The only rule that matters in our case is '''VYCQ(3)'''.
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| What VYCQ(3) asks is the following
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| Is A[ANY] conform to A[G]?
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| As we answer this question clearly with '''no''', the conversion is valid because all the other rules do not object either.
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| ====Example 2====
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| eweasel test: convert-to-current-type
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| <code>[eiffel,N]
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| class A[G]
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| convert
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| to_a: {A[STRING]}
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| feature
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| to_a: A[STRING]
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| end
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| </code>
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| In the case where G's actual type parameter is a subtype of STRING the two types are conform again.
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| The interesting rule is again '''VYCQ(3)''':
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| Is A[ANY] conform to A[STRING]?
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| This question is answered with '''no''' too. Therefore the conversion is valid.
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Revision as of 03:23, 19 January 2007
Warning: Warning: Article under development
Introduction
Warning: Warning: Article under development