Modifies vs. Replaces

[Michael Eager <eager at eagercon dot com>]

In his several emails, Todd Allen has offered a number of
scenarios in which a debugger might interpret and mis-interpret
a location description on a non-defining variable declaration.

To make my point succinctly, describing such a location description
as modifying the location description on a defining declaration
permits a debugger to decide how this modification is to be done.

My opinion is that in most (perhaps all) cases, augmenting the
location information of the defining declaration would be the
appropriate action for a debugger to take.  Todd, on the other hand, 
would decide that the appropriate modification is to replace the 
defining declaration's location information with the non-defining 
location.

In either case, this represents a modification to the location
information as described in the proposal.  As far as I can tell,
the proposal, as written, permits a debugger to act both as I
would feel is correct and as Todd would have it act.

Todd has suggested that the non-defining location information
must replace the location information of the defining declaration.
This would eliminate the interpretation that the two sets of
information were to be merged and require me to make the same 
design decisions in my debugger that he wishes to make in his.

Modifies permits a range of reasonable interpretations, which 
include replacement.  The converse is not true.

-- 
Michael Eager	 Eager Consulting     eager@eagercon.com
1960 Park Blvd., Palo Alto, CA 94306  650-325-8077