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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.lang.scheme
Subject: Re: on call by reference
Date: Wed, 20 Mar 2024 23:58:02 -0000 (UTC)
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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”.