SEDS for ISO 10303-11

[Jochen Haenisch]

Please, consider the SEDS report that is included below.
Best regards, Jochen Haenisch.

 <<SEDS_Express_20011129.txt>> 

____________________________________________________________
Jochen Haenisch			E-mail: Jochen.Haenisch at epmtech.jotne.com
EPM Technology AS		Home of the EXPRESS Data Manager
P.O Box 6629 Etterstad		Tel: Int + 47 23 17 17 26
N-0607 Oslo				Fax: Int + 47 23 17 17 01  
Norway					Web:  http://www.epmtech.jotne.com

-------------- next part --------------
Section 1. GENERAL INFORMATION (completed by SEDS Coordinator):
SEDS Report Issue Number:
Date Submitted: 2001/11/29
Status and date:
SEDS Team Leader:
SEDS Team Members:

Section 2. ENHANCEMENT AND DISCREPANCY INFORMATION (completed by
author of SEDS Report): Author: Jochen Haenisch, EPMT
(jochen.haenisch at epmtech.jotne.com) Submitted by: Norway
Part/Clause Affected by the Issue: ISO/IS 10303-11 (Clause 15.25 TypeOf - general function)
Other Parts Affected by the Issue:
Abstract: Ambiguous requirements
Problem Description:
The specification of the contents of the set of strings that shall be
returned by TYPEOF seems to be ambiguous.
Consider, for example, the following declaration:
 LOCAL
   x : NUMBER := 1.0;
 END_LOCAL;

On the one hand clause 15.25 states:
"Result : The contents of the returned set of string values are the names
(in upper case) of all types the value V is a member of."
The returned set of strings should then be for TYPEOF(x) for the example above:
    ['NUMBER','REAL'].

On the other hand clause 15.25 provides an algorithm for finding the set of
strings that states:
"It (editor comment: the returned set of string values) may be derived by
the following algorithm (which is given here for specification purposes
rather than to prescribe any particular type of implementation):
a) The result set is initialized using the type name V belongs to (by declaration), ...
b) Repeat until the list stops growing:
    1) Repeat for all names in the result set:
        - if the current name is the name of a simple data type: skip;
        - ...
"
With this the example above would only return:
    ['NUMBER'].

The algorithm does not seem to allow the name of the really instantiated type
to be returned by TYPEOF. No other concept in P11 seems to do that instead
either.

Conditions Under Which the Issue Was Discovered: EXPRESS software development

Proposed Solution (Optional):
Improve the wording of clause 15.25 to make clear that TYPEOF shall always
also return the name of the instantiated type, not only of the declared type.

Additional Notes:

Section 3. RESPONSE INFORMATION (completed by SEDS Team Leader):
Accepted/Rejected (date):
If Accepted, Resolution:

If Rejected, Reason:
Solution:
Comments:

Section 4. FOLLOW-UP INFORMATION (completed by WG Convener):
Class:
Priority:
Impact of Change: Require a TC to incorporate the change
Further Action Required:
Action Required by SEDS Coordinator/WG Conveners/QC/SC4: