Issue 4336: Hole in trader constraint language (zz-trader)
Source: Triodia Technologies Pty Ltd (Mr. Michi Henning, michi(at)triodia.com)
Nature: Uncategorized Issue
Severity: 
Summary: We have a hole in the trader constraint language:

	interface I1 {
		enum { red, green };
	};

	interface I2 {
		enum { green, red };
	};

The expression

	$.field_name == red

is ambiguous because it's not clear which red is meant. You could argue
that the type of the field on the left will identify what type should
apply for the enumerator on the right. However, that doesn't solve the
problem because

	red == red

is a valid expression.

Attempts to solve the problem by using a scoped name don't work:

	$.field_name == I1::red

That's because the grammar does not allow the use of the :: operator.
Resolution: 
Revised Text: 
Actions taken:
June 5, 2001: received issue
Discussion: 

End of Annotations:=====
Date: Tue, 5 Jun 2001 10:15:49 +1000 (EST)
From: Michi Henning <michi.henning@iona.com>
To: issues@omg.org
Subject: Hole in trader constraint language
Message-ID: <Pine.HPX.4.05.10106051012180.5208-100000@bobo.ooc.com.au>
Organization: IONA Technologies
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
X-UIDL: e<f!!*2o!!QRM!!\~pd9

We have a hole in the trader constraint language:

   interface I1 {
	     enum { red, green };
	     };

	     interface I2 {
		       enum { green, red };
		       };

The expression

    $.field_name == red

is ambiguous because it's not clear which red is meant. You could
argue
that the type of the field on the left will identify what type should
apply for the enumerator on the right. However, that doesn't solve the
problem because

	red == red

is a valid expression.

Attempts to solve the problem by using a scoped name don't work:

	 $.field_name == I1::red

That's because the grammar does not allow the use of the :: operator.

					  Cheers,

												Michi.
--
Michi Henning                             +61 7 3324 9633
Chief CORBA Scientist                     +61 4 1118 2700 (mobile)
IONA Technologies                         +61 7 3324 9799 (fax)
Total Business Integration
http://www.ooc.com.au/staff/michi