[sv-bc] Localparam in parameter_port_list???

hi sv-bc,

a recent discussion on sv-ec about places where "parameter" really
means "localparam" has reminded me of something that has always
seemed very odd to me, and the LRM merge could provide an opportunity
to fix.

Consider the following simple (and, I think, legal) example:

  module decoder(A, Y);
    parameter N_inputs = 3;
    localparam N_outputs = 1 << N_inputs;
    input [N_inputs-1:0] A;
    output [N_outputs-1:0] Y;
    ...

Now let's try to give that an ANSI-style parameter and
port list...

  module decoder
    #(parameter N_inputs = 3, localparam N_outputs = 1<<N_inputs)
    (input [N_inputs-1:0] A, output [N_outputs-1:0] Y);
    ...

But the existing BNF forbids the use of localparam in a 
parameter_port_list.  I was not around at the time this was
discussed, and it's always mystified me why it's forbidden;
I have often encountered situations where I would like to be able
to do it.  Is there some obvious objection that I have missed?

I would be fine with a restriction that all parameters must appear
before any localparams in such a port list.  Given that minor
restriction, I can't see why it would pose any problem.
-- 
Jonathan Bromley, Consultant

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