VHDL Issue Number:      0079
Classification:         Language Definition Problem
Language Version:       VHDL-87
Summary:                The LRM does not specify where the universal operators
                        are defined.
Related Issues:         None.
Relevant LRM Sections:  7.5, 10
Key Words and Phrases:  Universal operator, visibility
Current Status:         ISAC-Approved
1076-1993 Disposition:  Closed (All Issues Completely Addressed)
Disposition Rationale:  LRM was updated.
Superseded By:          N/A
-----------------------
Date Submitted:         1989/02/10
Author of Submission:   Doug Dunlop
Author's Affiliation:   Intermetrics, Inc.
Author's Post Address:  4733 Bethesda Ave #415
                        Bethesda, MD  20814
Author's Phone Number:  (301) 657-3775
Author's Fax Number:    
Author's Net Address:   dunlop@inmet.inmet.com
-----------------------
Date Analyzed:          1991/03/15
Author of Analysis:     Oz Levia
Revision Number:        $Revision: 1.9 $
Date Last Revised:      $Date: 1995/08/03 17:18:35 $


Description of Problem
----------------------
Visibility of declarations in VHDL depends on where the declaration appears.
The LRM does not specify where the operators discussed in LRM 7.5 are declared.


Proposed Resolution
-------------------
As in Ada, we assume these operators are defined in STANDARD.  Thus, for
example, the equality operator for universal_integer is a valid meaning for the
subexpression

        P."="(1, 1)

if and only if P denotes the package STD.STANDARD.


VASG-ISAC Analysis & Rationale
------------------------------
Yes.  The LRM should make it clear that the predefined operators are declared
in package STANDARD, and that the universal operators are declared in the same
package too.


VASG-ISAC Recommendation for IEEE Std 1076-1987
-----------------------------------------------
It should be assumed that the declaration of a predefined operator for any of
the types declared in STANDARD occurs immediately after the declaration of that
type in STANDARD.  It should also be assumed that the declaration of the
universal operators occurs immediately after the declaration of type
SEVERITY_LEVEL and before the declaration of type INTEGER.

At the end of Section 7.2, another paragraph should be added:

        "Operators which are predefined for the predefined types in
        package STANDARD, as described in the following sections, are
        assumed to be declared immediately after the declaration of the
        type in package STANDARD."

And in Section 7.5 another paragraph should be added after the table:

        "All the predefined universal operators should be assumed
        declared in package STANDARD after the declaration of type
        SEVERITY_LEVEL."


VASG-ISAC Recommendation for Future Revisions
---------------------------------------------
Add the above language in to the LRM.