. I hope you are able to see my point here.

Yes I can. My untested, typed into the browser, attempt to modify the original safe_set() function to demonstrate the idea that there is no advantage to using a mirrored data structure was broken. Sorry.

For real usage it would have to be something more like this:

sub safe_set {
    my( $ref, $k, $v ) = @_;
    die 'Bad first arg' unless ref( $ref ) eq 'HASH';
    
    if( exists $ref->{ $k } 
    and ref( $ref->{ $k } ) eq 'SCALAR'
    and is_shared( $ref->{ $k } )    
    ) {
        lock ${ $ref->{$k} };
        ${ $ref->{$k} } = $v;
    }
    else {
        lock $ref;
        $ref->{ $k } = \my $vs :shared = $v;
    }
}

[download]

Test, fix-up and sweeten to taste.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^7: Avoid Locking Entire Hashes by BrowserUk
in thread Avoid Locking Entire Hashes by jagan_1234

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