Subject: Re: std_logic_1164: CP-010 and numeric_std:Rob_P1
From: Rob Anderson (rob@reawebtech.com)
Date: Fri Dec 06 2002 - 23:19:26 PST
Comments below...
Peter Ashenden wrote:
> Jim,
>
> The problem with _moving_ the std_match functions from numeric_std to
> std_logic_1164 is that models that refer to numeric_std.std_match
> (either with selected names or via a use clause) would break.
This sort of thing happens all the time in VHDL 1987, C++, etc. People
work around the problem by using the old packages. I would prefer to
to the right thing, cleaning this up for the future. Vendors like
Model Tech and Synopsys will allow mixing old and new versions of
packages, VHDL '87, VHDL'93, etc. I think David B. started this
idea that something would break, it is not clear to me. In any
case, we would all still be using VHDL'87 by that logic.
>
> The problem with _copying_ the functions to std_logic_1164 is that you
> would then have homographs in the two packages, and models that use (in
> the use clause sense) both packages and refer to std_match would break.
>
> Hence my proposal to call the functions in std_logic_1164 match instead
> of std_match. You could add match as an alias for std_match in
> numeric_std if you want consistency of naming across the packages for
> new models.
>
> Cheers,
>
> PA
>
>
> On Sat, 2002-12-07 at 13:01, Jim Lewis wrote:
>
>>CP-010 Analyzed Add match functions like numeric_std.std_match
>>http://www.eda.org/vhdl-std-logic/proposals/CP-010-match-functions.txt
>>
>>In numeric_std, it was proposed in proposal Rob_P1/P2
>>(http://www.eda.org/vhdlsynth/pilot/hm/0026.html), that
>>the std_match functions for std_ulogic, std_logic_vector, and
>>std_ulogic_vector be moved to std_logic_1164.
>>
>>This would satisify CP-010 and Rob_P2. Is this a move that
>>everyone would support? Otherwise, CP-010 proposes adding a match
>>function to std_logic_1164. This means that we should add a
>>match function to numeric_std. There is more meaning to a
>>function when it is globally used.
>>
>>Cheers,
>>Jim
>>
>>--
>>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>Jim Lewis
>>Director of Training mailto:Jim@SynthWorks.com
>>SynthWorks Design Inc. http://www.SynthWorks.com
>>1-503-590-4787
>>
>>Expert VHDL Training for Hardware Design and Verification
>>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
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