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From: "Nasser M. Abbasi" <nma@12000.org>
Newsgroups: comp.lang.ada
Subject: Re: calling function but ignoring results
Date: Fri, 2 Jul 2021 20:22:55 -0500
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On 6/29/2021 2:25 PM, Matt Borchers wrote:
> It is not very often that ignoring a function result is okay, but I have run across many instances of the following block structure in code over the years:
> 
> declare
>      dont_care : BOOLEAN;
> begin
>      dont_care := foo( x, y );
> end;
> 
> I also see the procedure wrapper used in some cases -- usually when exported in a package specification:
> 
> procedure FOO( x, y ) is
>      b : BOOLEAN;
> begin
>      b := foo( x, y );
> end FOO;
> 

fyi, Matlab had this for years:

https://www.mathworks.com/help/matlab/matlab_prog/ignore-function-outputs.html

"
This example shows how to ignore specific outputs from a function using the tilde (~) operator.
To ignore function outputs in any position in the argument list, use the tilde operator. For example, ignore the first output using a tilde.

    [~,name,ext] = fileparts(helpFile);

"

--Nasser