Issue 19121: Imprecise result types of resolveIn expressions (qvt-rtf)
Source:  (, )
Nature: Revision
Severity: Significant
Summary: Section 8.2.1.22 ResolveExp states the following about the result type of a resolve expression:


"If no target variable is provided, the type is either Object (the type representing all types, see Section 8.3.1) either a Sequence of Objects - depending on the multiplicity."


On top of that, Section 8.2.1.23 ResolveInExp states:


"The type of a ResolveInExp expression is computed using the same rules as for the type of a ResolveExp."


In case of a ResolveInExp, why can't we obtain the result type from the respective mapping?


Consider the following example 


mapping EClass :: EClass2EPackage() : EPackage 

The result of any resolveIn expression for that mapping is necessarily a subtype of EPackage. No need to cast this up to Object.
Resolution: OclAny rather Object is of course the top type
Revised Text: In 8.2.1.23 ResolveInExp replace
The type of a ResolveInExp expression is computed using the same rules as for the type of a ResolveExp.
by
Type of a resolveIn expression
The type of a ResolveInExp expression depends on the type of the ‘target’ variable, the 'inMapping' operation
and on the multiplicity indication (the ‘one’ property). The overall returned type is specified in terms of an
intermediate resolved type.
If a 'target' variable is provided, the resolved-type is the type of the 'target' variable
Otherwise if an 'inMapping' is provided, .the resolved-type is the type of the 'inMapping'.
Otherwise the resolved-type is Object (the type representing all types, see Section 8.3.1).
If ‘one’ is true, the returned type is the resolved-type. Otherwise, the returned type is a Sequence of the
resolved-type.
Actions taken:
November 22, 2013: received issue
July 15, 2014: closed issue
Discussion: 

End of Annotations:=====

m: webmaster@omg.org
Date: 22 Nov 2013 04:16:26 -0500
To: <issues@omg.org>
Subject: Issue/Bug Report


*******************************************************************************
Name:            Christopher Gerking
Employer:        University of Paderborn
mailFrom:        christopher.gerking@upb.de
Terms_Agreement: I agree
Specification:   Meta Object Facility (MOF) 2.0 Query/View/ Transformation Specification
Section:         8.2.1.23 ResolveInExp
FormalNumber:    formal/2011-01-01
Version:         1.1
Doc_Year:        2011
Doc_Month:       January
Doc_Day:         01
Page:            101
Title:           Imprecise result types of resolveIn expressions
Nature:          Revision
Severity:        Significant
CODE:            3TMw8
B1:              Report Issue
Remote Name:     nb-sch-fs782-1.cs.uni-paderborn.de
Remote User:     
HTTP User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.57 Safari/537.36
Time:            04:16 AM


Description:


Section 8.2.1.22 ResolveExp states the following about the result type of a resolve expression:


"If no target variable is provided, the type is either Object (the type representing all types, see Section 8.3.1) either a Sequence of Objects - depending on the multiplicity."


On top of that, Section 8.2.1.23 ResolveInExp states:


"The type of a ResolveInExp expression is computed using the same rules as for the type of a ResolveExp."


In case of a ResolveInExp, why can't we obtain the result type from the respective mapping?


Consider the following example 


mapping EClass :: EClass2EPackage() : EPackage 

The result of any resolveIn expression for that mapping is necessarily a subtype of EPackage. No need to cast this up to Object.