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From: Schol-R-LEA <alicetrillianosako@gmail.com>
Newsgroups: comp.lang.scheme
Subject: Re: on call by reference
Date: Wed, 20 Mar 2024 21:00:20 -0400
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Lawrence D'Oliveiro:
> On Wed, 20 Mar 2024 10:57:18 -0400, Schol-R-LEA wrote:
> 
>> Languages such as C and C++ are interesting in this regard, as they have
>> only call-by-value semantics, but also support passing explicit
>> pointers, which allows them to simulate call-by-reference semantics by
>> the passing of explicit pointers.
> 
> C++ allows “references”, where the “pointer” part is no longer explicit.
> E.g.
> 
>      ResType Func
>        (
>          ArgType & Arg
>        )
>        {
>          ...
>        } /*Func*/
> 
> But of course this is not tied to function arguments at all, and can be
> used elsewhere, e.g.
> 
>      int A;
>      int & const B = A;
> 
> Now any assignment to “B” actually changes the value of “A”.


I had forgotten about C++ opaque references. Thank you for pointing that 
out.