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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.forth
Subject: Re: Quotations
Date: Sun, 05 Jun 2016 21:20:59 -0700
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Paul Rubin <no.email@nospam.invalid> writes:
> Hmm, so maybe it's ok to call the closure after the parent has returned,
> if there are no captured reference args.

I just tried modifying a captured-by-value variable inside a C++ lambda
and got a compile time error saying I'd tried to change a read-only
variable.  Also, it looks like the value is copied to the closure at the
time the closure is made (changes between calls aren't reflected in the
later calls).  So I guess that explains.  The code I tested:

    #include <iostream>

    main() {
      int n = 7;
      auto clo = [n]() {
        std::cout << "n: " << n << "\n";
        return 1;
      };
      clo();
      n++;
      clo();
    }

It prints "n: 7" twice.

I think this is more complicated behaviour than one would expect to find
in Forth.