Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!aero-c!aero!ivan
From: ivan@aero.aero.org (Ivan Filippenko)
Newsgroups: comp.lang.vhdl
Subject: parameter passing
Message-ID: <1991Feb27.201530.6434@aero.org>
Date: 27 Feb 91 20:15:30 GMT
Sender: news@aero.org
Reply-To: ivan@aero.aero.org (Ivan Filippenko)
Organization: The Aerospace Corporation
Lines: 20

I'm trying to figure out if I have the correct understanding of the
subprogram parameter-passing mechanism defined by the VHDL LRM.

To me, it appears thus:

    constant or variable parameter:

      if scalar or access type:  pass by copy
      if array or record:        pass by copy or reference (impl. defined)

    signal parameter:  pass by reference
                       (for signal and/or driver, depending on mode)

The LRM seems pretty clear on the matter of constant and variable
parameters, but I'm not certain of my interpretation in the case of
signal parameters.

Corroboration or clarification, anyone, please ?

Thanks a lot  --   Ivan Filippenko  (ivan@aerospace.aero.org)