A trip down memory lane ...

I reached across my desk and grabbed my original (pink) version of the Camel book. After blowing off a decade or two's worth of dust, I had a look around.

[Note: The printing history shows Jan. 1991 as "First Edition", then Aug. 1991 and Mar. 1992 as "Minor corrections". It would be a fair assumption that I have the more recent of those; page numbers below may be out by one or two for those with other versions.]

In "Chapter 3 The Gory Details" (pp. 65-121); under the "Packages" section (pp.119-121); I found on page 120: 

    local(*foo) = *bar;
    local($_main{'foo'}) = $_main{'bar'};

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... the *foo is more efficient because it does the symbol table lookup once at compile time ...

Also of nostalgic interest was the use of $main'var instead of $main::var. I haven't used the former version in over 20 years; however, it's still valid: 

$ cat pm_11137628_pkg_sep.pl
use strict;
use warnings;

our $x = 42;
print $], "\n";
print $main'x, "\n";
print $main::x, "\n";

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$ perl pm_11137628_pkg_sep.pl
5.034000
42
42

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"foo(*arr1,*arr2)"

Under the "Subroutines" section (pp. 99-102); on page 99; I note a small syntax change is required:

"A subroutine is called using the do operator or the & operator. The & operator is the preferred form."

However, other than that small syntax change, the gist of what you wrote is correct. There's an example on page 102: 

    sub arrayadd {
        local(*a, *b) = @_;
        ...
    }
    
    @foo = (1,2,3);
    @bar = (10,20,30);
    @totals = &arrayadd(*foo, *bar);

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[Disclaimer: Everything I've quoted from the book needed to be entered by hand. I believe it's all correct but apologise in advance for any typos that may have crept in.]

The "trip down memory lane" concludes. I hope that was an interesting read. I do acknowledge that it was way off-topic with respect to the OP subject.

— Ken

In reply to Re^5: POD for use feature 'declared_refs' wrong by kcott
in thread POD for use feature 'declared_refs' wrong by LanX

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