RE: [sv-bc] Local parameters in parameter-port-list (Mantis 1134)

Jonathan,

I see no difference between this and in the handling of port directions.
If you specify a port direction, all declarations that follow retain
that direction until another direction is specified. Same for types. So
what's different about parameter/localparam? 

Dave


-----Original Message-----
From: owner-sv-bc@server.eda.org [mailto:owner-sv-bc@server.eda.org] On
Behalf Of Jonathan Bromley
Sent: Tuesday, August 21, 2007 8:22 AM
To: sv-bc@server.eda-stds.org
Subject: RE: [sv-bc] Local parameters in parameter-port-list (Mantis
1134)

hi BC,

The minutes of your meeting of 23 July say the following about 1134:

   Consensus that localparams be skipped when dealing with
   override by position.  This is the same as non-ANSI-style
   parameter usage currently enabled and relaxes requirement
   in the current proposal that they appear at the end of the list.
   Update wording and BNF accordingly.

This can be achieved rather easily by deleting all my proposed
BNF changes and instead making this change:

parameter_port_declaration ::=
    parameter_declaration
  | local_parameter_declaration           // added branch
  | data_type list_of_param_assignments
  | *type* list_of_type_assignments

provided the changes in Mantis 979 are also implemented.

However, I think this has an unfortunate side-effect.
Consider

  module foo
   #(
      parameter P = 3,
      localparam L = P+1,
      type T = logic [P:0],
      T PT = 5
    ) ...

Would you say that T is a localparam or a parameter?
What about PT?  And what would users think?
(For what it's worth, I think that both T and PT 
are localparams, but I think users might be very 
surprised to find they can't override T.)

This is precisely the confusion I was trying to avoid by 
requiring all localparams to be at the end of the list.

If you're OK with it, then I'll go ahead and update the
proposal; the new proposal will state as a prerequisite
that the changes of Mantis 979 be implemented.
-- 
Jonathan Bromley, Consultant

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