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[QUOTE="rickman, post: 3523118"]
Given that statement, how do I apply this when working with
constrained integers...

I have a function to perform a "shift" operation on an integer,

function sllint (x, sh : natural) return natural is
  begin
	return x*(2**sh);
  end sllint;

I am using it with a constrained integer,

SIGNAL Addr			: NibbInt;

where

subtype NibbInt		is Integer range 0 to 2**4-1;

usage,

Addr	<= sllint(Addr, CTPDATAWDTH) + to_nat(Scfg_Din);

where Scfg_Din is an SLV (1 downto 0) and CTPDATAWDTH is an integer
constant of 2.

I am not clear on what happens when I shift the value of Addr left by
2 and significant bits extend beyond the defined range.  I thought
about defining an overloaded operator for shifting NibbInt which would
use the mod operator, but you say the subtype won't be used for
overloading.  So it would just use the sllint operator defined for
integer anyway.

I don't want to have to pass into the function the range of the
parameter.  The usage of the function just gets too messy.  I guess I
could use an sllnib operator, but I would prefer not to have to pre-
select the function and the compiler select it as an overloaded
function.

How am I looking at this wrong?  Shouldn't I be able to do this?

Rick
[/QUOTE]

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